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Shiho M, Akashita G, Nakatani E, Tanaka S, Yamada S, Okura T. Predicting muscarinic receptor occupancy in human bladder mucosa from urinary concentrations of antimuscarinic agents for overactive bladder. Drug Metab Pharmacokinet 2024; 56:100998. [PMID: 38583388 DOI: 10.1016/j.dmpk.2024.100998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 11/28/2023] [Accepted: 01/06/2024] [Indexed: 04/09/2024]
Abstract
To assess the pharmacologically relevant and selective muscarinic receptor occupancy in the bladder mucosa, we considered not only plasma drug concentrations but also urinary drug concentrations. The purpose of this study was to predict muscarinic receptor occupancy in the human bladder mucosa based on urinary concentrations in response to clinical dosages of antimuscarinic agents used to treat overactive bladder. The calculated mean plasma or serum unbound steady state concentrations were 0.06-11 nM in clinical dosages of five antimuscarinic agents. Urinary concentrations calculated from the mean plasma or serum and renal clearance ranged between 19 nM and 2 μM, which were >10-fold higher than the Ki values for bladder muscarinic receptors excluding propiverine. Bladder mucosal muscarinic receptor occupancy estimated from the urinary concentrations and the Ki values was >90 % at a steady state in clinical dosages of five antimuscarinic agents. The bladder muscarinic receptor occupancy was higher than that in the parotid gland calculated based on the mean plasma or serum unbound concentrations and Ki values for muscarinic receptors in the parotid gland. These results suggest that sufficient and selective muscarinic receptor occupancy by antimuscarinic agents, to exert pharmacological effects, in the bladder mucosa can be predicted using urinary concentrations.
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Affiliation(s)
- Mizuki Shiho
- Faculty of Pharma-Science, Teikyo University, Japan
| | | | | | | | - Shizuo Yamada
- Center for Pharma-Food Research (CPFR), Graduate School of Pharmaceutical Sciences, University of Shizuoka, Japan
| | - Takashi Okura
- Faculty of Pharma-Science, Teikyo University, Japan.
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2
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Lopresti BJ, Royse SK, Mathis CA, Tollefson SA, Narendran R. Beyond monoamines: I. Novel targets and radiotracers for Positron emission tomography imaging in psychiatric disorders. J Neurochem 2023; 164:364-400. [PMID: 35536762 DOI: 10.1111/jnc.15615] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
With the emergence of positron emission tomography (PET) in the late 1970s, psychiatry had access to a tool capable of non-invasive assessment of human brain function. Early applications in psychiatry focused on identifying characteristic brain blood flow and metabolic derangements using radiotracers such as [15 O]H2 O and [18 F]FDG. Despite the success of these techniques, it became apparent that more specific probes were needed to understand the neurochemical bases of psychiatric disorders. The first neurochemical PET imaging probes targeted sites of action of neuroleptic (dopamine D2 receptors) and psychoactive (serotonin receptors) drugs. Based on the centrality of monoamine dysfunction in psychiatric disorders and the measured success of monoamine-enhancing drugs in treating them, the next 30 years witnessed the development of an armamentarium of PET radiopharmaceuticals and imaging methodologies for studying monoamines. Continued development of monoamine-enhancing drugs over this time however was less successful, realizing only modest gains in efficacy and tolerability. As patent protection for many widely prescribed and profitable psychiatric drugs lapsed, drug development pipelines shifted away from monoamines in search of novel targets with the promises of improved efficacy, or abandoned altogether. Over this period, PET radiopharmaceutical development activities closely paralleled drug development priorities resulting in the development of new PET imaging agents for non-monoamine targets. Part one of this review will briefly survey novel PET imaging targets with relevance to the field of psychiatry, which include the metabotropic glutamate receptor type 5 (mGluR5), purinergic P2 X7 receptor, type 1 cannabinoid receptor (CB1 ), phosphodiesterase 10A (PDE10A), and describe radiotracers developed for these and other targets that have matured to human subject investigations. Current limitations of the targets and techniques will also be discussed.
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Affiliation(s)
- Brian J Lopresti
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah K Royse
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chester A Mathis
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Savannah A Tollefson
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rajesh Narendran
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Departments of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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3
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Redmond JS, Stang BV, Schlipf JW, Christensen JM. Pharmacokinetics of diphenhydramine following single-dose intravenous and oral administration in non-fasted adult horses. J Vet Pharmacol Ther 2021; 45:188-195. [PMID: 34921427 DOI: 10.1111/jvp.13041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Revised: 11/14/2021] [Accepted: 12/12/2021] [Indexed: 11/30/2022]
Abstract
Diphenhydramine is an H1 receptor antagonist used to control urticaria and other allergic signs caused by type I hypersensitivity reactions in horses (Equus caballus). Limited studies have been conducted on pharmacokinetics of this drug in horses, with no studies involving oral formulations. Our study investigated pharmacokinetics of an oral diphenhydramine formulation compared to intravenous administration in non-fasted adult horses. Six healthy horses underwent a single administration of three different doses of diphenhydramine (1 mg/kg intravenously, 1 mg/kg intragastrically, and 5 mg/kg intragastrically) with a two-week washout period between doses. Bioavailability of intragastric diphenhydramine was less than one percent and six percent for 1 mg/kg and 5 mg/kg intragastric doses, respectively. This poor bioavailability is similar to what is reported in dogs. Two of six horses experienced transient side effects after intravenous diphenhydramine administration, emphasizing the need for determining therapeutic plasma levels in efforts to determine the lowest effective dose minimizing risk of adverse effects. The main conclusion of our study was that oral diphenhydramine at doses up to 5 mg/kg are unlikely to achieve therapeutic plasma levels in adult horses.
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Affiliation(s)
- Jeremy S Redmond
- Department of Clinical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, USA
| | - Bernadette V Stang
- Department of Clinical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, USA
| | - John W Schlipf
- Department of Clinical Sciences, Carlson College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, USA
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4
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Yanai K, Yoshikawa T, Church MK. Efficacy and Safety of Non-brain Penetrating H 1-Antihistamines for the Treatment of Allergic Diseases. Curr Top Behav Neurosci 2021; 59:193-214. [PMID: 34622396 DOI: 10.1007/7854_2021_265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
H1 receptor antagonists, known as H1-antihistamines (AHs), inactivate the histamine H1-receptor thereby preventing histamine causing the primary symptoms of allergic diseases, such as atopic dermatitis, pollinosis, food allergies, and urticaria. AHs, which are classified into first-generation (fgAHs) and second-generation (sgAHs) antihistamines, are the first line of treatment for allergic diseases. Although fgAHs are effective, they cause adverse reactions such as potent sedating effects, including drowsiness, lassitude, and cognitive impairment; anticholinergic effects, including thirst and tachycardia. Consequently, the use of fgAHs is not recommended for allergic diseases. Today, sgAHs, which are minimally sedating and, therefore, may be used at more effective doses, are the first-line treatment for alleviating the symptoms of allergic diseases. Pharmacologically, the use of sedating fgAHs is limited to antiemetics, anti-motion sickness drugs, and antivertigo drugs. The use of histamine H1-receptor occupancy (H1RO) based on positron emission tomography (PET) has been developed for the evaluation of brain penetrability. Based on the results of the H1RO-PET studies, non-brain-penetrating AHs (nbpAHs) have recently been reclassified among sgAHs. The nbpAHs are rapidly acting and exhibit minimal adverse reactions and, thus, are considered first-line drugs for allergic diseases. In this review, we will introduce recent topics on the pharmacodynamics and pharmacokinetics of AHs and make recommendations for the use of nbpAHs as first-line treatment options for allergic diseases.
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Affiliation(s)
- Kazuhiko Yanai
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan. .,Cyclotron and Radioisotope Center (CYRIC), Tohoku University, Sendai, Japan.
| | - Takeo Yoshikawa
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | - Martin K Church
- Department of Dermatology and Allergy, Charitè-Universitätsmedizin, Berlin, Germany
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5
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Falkenstein M, Elek M, Stark H. Chemical Probes for Histamine Receptor Subtypes. Curr Top Behav Neurosci 2021; 59:29-76. [PMID: 34595743 DOI: 10.1007/7854_2021_254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Ligands with different properties and different selectivity are highly needed for in vitro and in vivo studies on the (patho)physiological influence of the chemical mediator histamine and its receptor subtypes. A selection of well-described ligands for the different receptor subtypes and different studies is shown with a particular focus on affinity and selectivity. In addition, compounds with radioactive or fluorescence elements will be presented with their beneficial use for other species or different investigations.
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Affiliation(s)
- Markus Falkenstein
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany
| | - Milica Elek
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany
| | - Holger Stark
- Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University Düsseldorf, Duesseldorf, Germany.
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6
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Takamura Y, Kakuta H. In Vivo Receptor Visualization and Evaluation of Receptor Occupancy with Positron Emission Tomography. J Med Chem 2021; 64:5226-5251. [PMID: 33905258 DOI: 10.1021/acs.jmedchem.0c01714] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Positron emission tomography (PET) is useful for noninvasive in vivo visualization of disease-related receptors, for evaluation of receptor occupancy to determine an appropriate drug dosage, and for proof-of-concept of drug candidates in translational research. For these purposes, the specificity of the PET tracer for the target receptor is critical. Here, we review work in this area, focusing on the chemical structures of reported PET tracers, their Ki/Kd values, and the physical properties relevant to target receptor selectivity. Among these physical properties, such as cLogP, cLogD, molecular weight, topological polar surface area, number of hydrogen bond donors, and pKa, we focus especially on LogD and LogP as important physical properties that can be easily compared across a range of studies. We discuss the success of PET tracers in evaluating receptor occupancy and consider likely future developments in the field.
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Affiliation(s)
- Yuta Takamura
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
| | - Hiroki Kakuta
- Division of Pharmaceutical Sciences, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 1-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan
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7
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Kárpáti A, Yoshikawa T, Naganuma F, Matsuzawa T, Kitano H, Yamada Y, Yokoyama M, Futatsugi A, Mikoshiba K, Yanai K. Histamine H 1 receptor on astrocytes and neurons controls distinct aspects of mouse behaviour. Sci Rep 2019; 9:16451. [PMID: 31712580 PMCID: PMC6848115 DOI: 10.1038/s41598-019-52623-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 10/21/2019] [Indexed: 01/03/2023] Open
Abstract
Histamine is an important neurotransmitter that contributes to various processes, including the sleep-wake cycle, learning, memory, and stress responses. Its actions are mediated through histamine H1–H4 receptors. Gene knockout and pharmacological studies have revealed the importance of H1 receptors in learning and memory, regulation of aggression, and wakefulness. H1 receptors are abundantly expressed on neurons and astrocytes. However, to date, studies selectively investigating the roles of neuronal and astrocytic H1 receptors in behaviour are lacking. We generated novel astrocyte- and neuron-specific conditional knockout (cKO) mice to address this gap in knowledge. cKO mice showed cell-specific reduction of H1 receptor gene expression. Behavioural assessment revealed significant changes and highlighted the importance of H1 receptors on both astrocytes and neurons. H1 receptors on both cell types played a significant role in anxiety. Astrocytic H1 receptors were involved in regulating aggressive behaviour, circadian rhythms, and quality of wakefulness, but not sleep behaviour. Our results emphasise the roles of neuronal H1 receptors in recognition memory. In conclusion, this study highlights the novel roles of H1 receptors on astrocytes and neurons in various brain functions.
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Affiliation(s)
- Anikó Kárpáti
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Takeo Yoshikawa
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan.
| | - Fumito Naganuma
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan.,Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, 1-15-1 Fukumuro, Miyagino-ku, Sendai, 983-8536, Japan
| | - Takuro Matsuzawa
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Haruna Kitano
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Yo Yamada
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Mariko Yokoyama
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | - Akira Futatsugi
- Department of Basic Medical Sciences, Kobe City College of Nursing, 3-4 Gakuen-nishi-machi, Nishi-ku, Kobe, 651-2103, Japan
| | - Katsuhiko Mikoshiba
- Shanghai Institute for Advanced Immunochemical Studies, ShanghaiTech University, Shanghai, 201210, China
| | - Kazuhiko Yanai
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
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8
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Nakamura T, Hiraoka K, Harada R, Matsuzawa T, Ishikawa Y, Funaki Y, Yoshikawa T, Tashiro M, Yanai K, Okamura N. Brain histamine H 1 receptor occupancy after oral administration of desloratadine and loratadine. Pharmacol Res Perspect 2019; 7:e00499. [PMID: 31338198 PMCID: PMC6624455 DOI: 10.1002/prp2.499] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/30/2019] [Accepted: 06/10/2019] [Indexed: 01/27/2023] Open
Abstract
Some histamine H1 receptor (H1R) antagonists induce adverse sedative reactions caused by blockade of histamine transmission in the brain. Desloratadine is a second-generation antihistamine for treatment of allergic disorders. Its binding to brain H1Rs, which is the basis of sedative property of antihistamines, has not been examined previously in the human brain by positron emission tomography (PET). We examined brain H1R binding potential ratio (BPR), H1R occupancy (H1RO), and subjective sleepiness after oral desloratadine administration in comparison to loratadine. Eight healthy male volunteers underwent PET imaging with [11C]-doxepin, a PET tracer for H1Rs, after a single oral administration of desloratadine (5 mg), loratadine (10 mg), or placebo in a double-blind crossover study. BPR and H1RO in the cerebral cortex were calculated, and plasma concentrations of loratadine and desloratadine were measured. Subjective sleepiness was quantified by the Line Analogue Rating Scale (LARS) and the Stanford Sleepiness Scale (SSS). BPR was significantly lower after loratadine administration than after placebo (0.504 ± 0.074 vs 0.584 ± 0.059 [mean ± SD], P < 0.05), but BPR after desloratadine administration was not significantly different from BPR after placebo (0.546 ± 0.084 vs 0.584 ± 0.059, P = 0.250). The plasma concentration of loratadine was negatively correlated with BPR in subjects receiving loratadine, but that of desloratadine was not correlated with BPR. Brain H1ROs after desloratadine and loratadine administration were 6.47 ± 10.5% and 13.8 ± 7.00%, respectively (P = 0.103). Subjective sleepiness did not significantly differ among subjects receiving the two antihistamines and placebo. At therapeutic doses, desloratadine did not bind significantly to brain H1Rs and did not induce any significant sedation.
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Affiliation(s)
- Tadaho Nakamura
- Division of Pharmacology, Faculty of MedicineTohoku Medical and Pharmaceutical UniversitySendaiJapan
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
| | - Kotaro Hiraoka
- Cyclotron and Radioisotope CenterTohoku UniversitySendaiJapan
| | - Ryuichi Harada
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
| | - Takuro Matsuzawa
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
| | - Yoichi Ishikawa
- Cyclotron and Radioisotope CenterTohoku UniversitySendaiJapan
| | | | - Takeo Yoshikawa
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
| | - Manabu Tashiro
- Cyclotron and Radioisotope CenterTohoku UniversitySendaiJapan
| | - Kazuhiko Yanai
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
| | - Nobuyuki Okamura
- Division of Pharmacology, Faculty of MedicineTohoku Medical and Pharmaceutical UniversitySendaiJapan
- Department of PharmacologyTohoku University Graduate School of MedicineSendaiJapan
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9
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Antihistamines for Allergic Rhinitis Treatment from the Viewpoint of Nonsedative Properties. Int J Mol Sci 2019; 20:ijms20010213. [PMID: 30626077 PMCID: PMC6337346 DOI: 10.3390/ijms20010213] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 12/26/2018] [Accepted: 12/29/2018] [Indexed: 12/21/2022] Open
Abstract
Antihistamines targeting the histamine H1 receptor play an important role in improving and maintaining the quality of life of patients with allergic rhinitis. For more effective and safer use of second-generation drugs, which are recommended by various guidelines, a classification based on their detailed characteristics is necessary. Antihistamines for first-line therapy should not have central depressant/sedative activities. Sedative properties (drowsiness and impaired performance) are associated with the inhibition of central histamine neurons. Brain H1 receptor occupancy (H1RO) is a useful index shown to be correlated with indices based on clinical findings. Antihistamines are classified into non-sedating (<20%), less-sedating (20–50%), and sedating (≥50%) groups based on H1RO. Among the non-sedating group, fexofenadine and bilastine are classified into “non-brain-penetrating antihistamines” based on the H1RO. These two drugs have many common chemical properties. However, bilastine has more potent binding affinity to the H1 receptor, and its action tends to last longer. In well-controlled studies using objective indices, bilastine does not affect psychomotor or driving performance even at twice the usual dose (20 mg). Upon selecting antihistamines for allergic rhinitis, various situations should be taken into our consideration. This review summarizes that the non-brain-penetrating antihistamines should be chosen for the first-line therapy of mild allergic rhinitis.
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10
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Hu W, Chen Z. The roles of histamine and its receptor ligands in central nervous system disorders: An update. Pharmacol Ther 2017; 175:116-132. [DOI: 10.1016/j.pharmthera.2017.02.039] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Kanamitsu K, Nozaki Y, Nagaya Y, Sugiyama Y, Kusuhara H. Quantitative prediction of histamine H1 receptor occupancy by the sedative and non-sedative antagonists in the human central nervous system based on systemic exposure and preclinical data. Drug Metab Pharmacokinet 2016; 32:135-144. [PMID: 28190755 DOI: 10.1016/j.dmpk.2016.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Revised: 10/28/2016] [Accepted: 11/07/2016] [Indexed: 12/15/2022]
Abstract
Significant histamine H1 receptor occupation in the central nervous system (CNS) is associated with sedation. Here we examined the time profiles of the H1 receptor occupancy (RO) in the CNS using sedative (diphenhydramine and ketotifen) and non-sedative (bepotastine and olopatadine) antagonists at their therapeutic doses by integrating in vitro and animal data. A pharmacokinetic model was constructed to associate plasma concentrations and receptor binding in the brain. Dissociation and association rate constants with the H1 receptor and plasma and brain unbound fractions were determined in vitro. Passive and active clearances across the blood-brain barrier (BBB) were estimated based on physicochemical properties and microdialysis studies in mice and monkeys. The estimated RO values were comparable with the reported values determined at time to maximum concentration (Tmax) of plasma by positron-emission tomography in humans. The simulation suggested that the predicted maximum ROs by bepotastine and olopatadine were greater than the reported values. Sensitivity analysis showed that active transport across BBB had a significant impact on the RO duration of the H1 antagonists examined. The present study demonstrated that modeling and simulation permits a reasonable RO estimation in the human CNS. Our findings will facilitate the development of CNS-acting drugs.
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Affiliation(s)
- Kayoko Kanamitsu
- Laboratory of Molecular Pharmacokinetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan; Tokushima Research Institute, Otsuka Pharmaceutical Co., Ltd., 463-10 Kagasuno, Kawauchi-cho, Tokushima-shi, Tokushima, 771-0192, Japan
| | - Yoshitane Nozaki
- Drug Metabolism and Pharmacokinetics Tsukuba, Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki, 300-2635, Japan
| | - Yoko Nagaya
- Drug Metabolism and Pharmacokinetics Tsukuba, Tsukuba Research Laboratories, Eisai Co., Ltd., 5-1-3 Tokodai, Tsukuba-shi, Ibaraki, 300-2635, Japan
| | - Yuichi Sugiyama
- Sugiyama Laboratory, RIKEN Innovation Center, Research Cluster for Innovation, RIKEN, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama-shi, Kanagawa, 230-0045, Japan
| | - Hiroyuki Kusuhara
- Laboratory of Molecular Pharmacokinetics, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
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12
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Wang XY, Lim-Jurado M, Prepageran N, Tantilipikorn P, Wang DY. Treatment of allergic rhinitis and urticaria: a review of the newest antihistamine drug bilastine. Ther Clin Risk Manag 2016; 12:585-97. [PMID: 27110120 PMCID: PMC4835134 DOI: 10.2147/tcrm.s105189] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Allergic rhinitis and urticaria are common allergic diseases that may have a major negative impact on patients' quality of life. Bilastine, a novel new-generation antihistamine that is highly selective for the H1 histamine receptor, has a rapid onset and prolonged duration of action. This agent does not interact with the cytochrome P450 system and does not undergo significant metabolism in humans, suggesting that it has very low potential for drug-drug interactions, and does not require dose adjustment in renal impairment. As bilastine is not metabolized and is excreted largely unchanged, hepatic impairment is not expected to increase systemic exposure above the drug's safety margin. Bilastine has demonstrated similar efficacy to cetirizine and desloratadine in patients with seasonal allergic rhinitis and, in a Vienna Chamber study, a potentially longer duration of action than fexofenadine in patients with asymptomatic seasonal allergic rhinitis. It has also shown significant efficacy (similar to that of cetirizine) and safety in the long-term treatment of perennial allergic rhinitis. Bilastine showed similar efficacy to levocetirizine in patients with chronic spontaneous urticaria and can be safely used at doses of up to fourfold higher than standard dosage (80 mg once daily). The fourfold higher than standard dose is specified as an acceptable second-line treatment option for urticaria in international guidelines. Bilastine is generally well tolerated, both at standard and at supratherapeutic doses, appears to have less sedative potential than other second-generation antihistamines, and has no cardiotoxicity. Based on its pharmacokinetic properties, efficacy, and tolerability profile, bilastine will be valuable in the management of allergic rhinitis and urticaria.
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Affiliation(s)
- Xue Yan Wang
- Department of Allergy, Beijing Shijitan Hospital, Capital Medical University, Beijing, People's Republic of China
| | | | - Narayanan Prepageran
- Department of Otorhinolaryngology, Head & Neck Surgery, University Malaya Faculty of Medicine, Kuala Lumpur, Malaysia
| | - Pongsakorn Tantilipikorn
- Rhinology and Allergy Division, Department of Otorhinolaryngology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - De Yun Wang
- Department of Otolaryngology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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13
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Farré M, Pérez-Mañá C, Papaseit E, Menoyo E, Pérez M, Martin S, Bullich S, Rojas S, Herance JR, Trampal C, Labeaga L, Valiente R. Bilastine vs. hydroxyzine: occupation of brain histamine H1 -receptors evaluated by positron emission tomography in healthy volunteers. Br J Clin Pharmacol 2015; 78:970-80. [PMID: 24833043 PMCID: PMC4243871 DOI: 10.1111/bcp.12421] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 05/08/2014] [Indexed: 12/16/2022] Open
Abstract
AIM A close correlation exists between positron emission tomography (PET)-determined histamine H1 -receptor occupancy (H1 RO) and the incidence of sedation. Antihistamines with H1 RO <20% are classified as non-sedating. The objective was to compare the H1 RO of bilastine, a second generation antihistamine, with that of hydroxyzine. METHODS This randomized, double-blind, crossover study used PET imaging with [(11) C]-doxepin to evaluate H1 RO in 12 healthy males (mean age 26.2 years), after single oral administration of bilastine (20 mg), hydroxyzine (25 mg) or placebo. Binding potentials and H1 ROs were calculated in five cerebral cortex regions of interest: frontal, occipital, parietal, temporal, insula. Plasma bilastine concentrations, subjective sedation (visual analogue scale), objective psychomotor performance (digital symbol substitution test), physiological variables and safety (adverse events, AEs), were also evaluated. RESULTS The mean binding potential of all five regions of interest (total binding potential) was significantly greater with bilastine than hydroxyzine (mean value 0.26 vs. 0.13, P < 0.01; mean difference and 95% CI -0.130 [-0.155, 0.105]). There was no significant difference between bilastine and placebo. Overall H1 RO by bilastine was significantly lower than that by hydroxyzine (mean value -3.92% vs. 53.95%, P < 0.01; mean difference and 95% CI 57.870% [42.664%, 73.075%]). There was no significant linear relationship between individual bilastine plasma concentrations and total binding potential values. No significant between-treatment differences were observed for sedation and psychomotor performance. Twenty-six non-serious AEs were reported. Sleepiness or sedation was not reported with bilastine but appeared in some subjects with hydroxyzine. CONCLUSIONS A single oral dose of bilastine 20 mg had minimal H1 RO, was not associated with subjective sedation or objective impairment of psychomotor performance and was devoid of treatment-related sedative AEs, thus satisfying relevant subjective, objective and PET criteria as a non-sedating antihistamine.
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Affiliation(s)
- Magí Farré
- Human Pharmacology and Neuroscience Research Unit, Hospital del Mar Medical Research Institute-IMIM, and Universidad Autónoma de Barcelona-UAB, Barcelona, Spain
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Hiraoka K, Tashiro M, Grobosch T, Maurer M, Oda K, Toyohara J, Ishii K, Ishiwata K, Yanai K. Brain histamine H1 receptor occupancy measured by PET after oral administration of levocetirizine, a non-sedating antihistamine. Expert Opin Drug Saf 2014; 14:199-206. [PMID: 25466429 DOI: 10.1517/14740338.2015.989831] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
OBJECTIVE Histamine H1 receptor (H1R) antagonists often have sedative side effects, which are caused by the blockade of the neural transmission of the histaminergic neurons. We examined the brain H1R occupancy (H1RO) and the subjective sleepiness of levocetirizine, a new second-generation antihistamine, comparing fexofenadine, another non-sedating antihistamine, as a negative active control. METHODS Eight healthy volunteers underwent positron emission tomography (PET) imaging with [(11)C]doxepin, a PET tracer that specifically binds to H1Rs, after a single oral administration of levocetirizine (5 mg), fexofenadine (60 mg) or placebo in a double-blind crossover study. Binding potential ratios and H1ROs in the cerebral cortices regions were calculated using placebo. Subjective sleepiness was assessed with the Line Analogue Rating Scale and the Stanford Sleepiness Scale. RESULTS There was no significant difference between the mean brain H1RO after levocetirizine administration (8.1%; 95% CI: -9.8 to 26.0%) and fexofenadine administration (-8.0%; 95% CI: -26.7 to 10.6%). Similarly, subjective sleepiness was not significantly different between the two antihistamines and placebo. Neither subjective sleepiness nor plasma concentrations was significantly correlated with the brain H1RO of the two antihistamines. CONCLUSION At therapeutic dose, levocetirizine does not bind significantly to the brain H1Rs and does not induce significant sedation.
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Affiliation(s)
- Kotaro Hiraoka
- Tohoku University, Cyclotron and Radioisotope Center, Division of Cyclotron Nuclear Medicine , 6-3, Aoba, Aramaki, Aoba-ku, Sendai, 980-8578 , Japan
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15
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Drowsiness and motor responses to consecutive daily doses of promethazine and loratadine. Clin Neurophysiol 2014; 125:2390-6. [DOI: 10.1016/j.clinph.2014.03.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 03/06/2014] [Accepted: 03/28/2014] [Indexed: 01/06/2023]
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van Ruitenbeek P, Vermeeren A, Mehta MA, Drexler EI, Riedel WJ. Antihistamine induced blood oxygenation level dependent response changes related to visual processes during sensori-motor performance. Hum Brain Mapp 2013; 35:3095-106. [PMID: 24142460 DOI: 10.1002/hbm.22387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 06/24/2013] [Accepted: 07/22/2013] [Indexed: 01/20/2023] Open
Abstract
The histaminergic involvement in selective processes underlying its role in human sensori-motor performance is largely unknown. Recently, selective effects of central H₁-inverse agonism on sensory visual processes were observed in electrophysiological--but not behavioral data; a discrepancy suggested to result from speeded response-choice related processes. This study attempts to establish the effects on visual processes and identify putative compensatory mechanisms related to increased visual and response-choice task demands by assessing H₁-inverse agonism induced changes in blood oxygenation level dependent (BOLD) response. Twelve participants received oral doses of dexchlorpheniramine 4 mg, lorazepam 1 mg, and placebo in a three-way crossover designed study. Brain activity was assessed for choice reaction time task performance in a 3 T magnetic resonance scanner 2 h after drug administration. Participants responded with their left or right hand and index or middle finger as indicated by the laterality of stimulus presentation and identity of the stimulus, respectively. Stimuli were intact or visually degraded and responses were compatible or incompatible with the laterality of stimulus presentation. Both dexchlorpheniramine and lorazepam affected the BOLD response in the occipital cortex indicating affected visual information processing. Dexchlorpheniramine decreased BOLD response in the dorsal precuneus and left precentral gyrus as part of a motor network, which however might not be interpreted as a compensatory mechanism, but may be the upstream consequence of impaired visual processing.
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Affiliation(s)
- Peter van Ruitenbeek
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands
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17
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The role of histamine receptors in the consolidation of object recognition memory. Neurobiol Learn Mem 2013; 103:64-71. [PMID: 23583502 DOI: 10.1016/j.nlm.2013.04.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 03/12/2013] [Accepted: 04/02/2013] [Indexed: 12/18/2022]
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18
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Funke U, Vugts DJ, Janssen B, Spaans A, Kruijer PS, Lammertsma AA, Perk LR, Windhorst AD. 11C-labeled and18F-labeled PET ligands for subtype-specific imaging of histamine receptors in the brain. J Labelled Comp Radiopharm 2013; 56:120-9. [DOI: 10.1002/jlcr.3038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 01/18/2013] [Accepted: 01/29/2013] [Indexed: 12/13/2022]
Affiliation(s)
| | - Danielle J. Vugts
- VU University Medical Center, Department of Radiology & Nuclear Medicine; Location Radionuclide Center; De Boelelaan 1085c; 1081; HV; Amsterdam; The Netherlands
| | - Bieneke Janssen
- VU University Medical Center, Department of Radiology & Nuclear Medicine; Location Radionuclide Center; De Boelelaan 1085c; 1081; HV; Amsterdam; The Netherlands
| | | | - Perry S. Kruijer
- BV Cyclotron VU; De Boelelaan 1081; 1081; HV; Amsterdam; The Netherlands
| | - Adriaan A. Lammertsma
- VU University Medical Center, Department of Radiology & Nuclear Medicine; Location Radionuclide Center; De Boelelaan 1085c; 1081; HV; Amsterdam; The Netherlands
| | - Lars R. Perk
- BV Cyclotron VU; De Boelelaan 1081; 1081; HV; Amsterdam; The Netherlands
| | - Albert D. Windhorst
- VU University Medical Center, Department of Radiology & Nuclear Medicine; Location Radionuclide Center; De Boelelaan 1085c; 1081; HV; Amsterdam; The Netherlands
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Kamei H, Isaji A, Noda Y, Ishikawa K, Senzaki K, Yamada K, Sugiura K, Tomita Y, Nabeshima T. Effects of single therapeutic doses of promethazine, fexofenadine and olopatadine on psychomotor function and histamine-induced wheal- and flare-responses: a randomized double-blind, placebo-controlled study in healthy volunteers. Arch Dermatol Res 2011; 304:263-72. [PMID: 22130869 PMCID: PMC3332365 DOI: 10.1007/s00403-011-1192-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Revised: 11/09/2011] [Accepted: 11/14/2011] [Indexed: 11/30/2022]
Abstract
Since most first-generation antihistamines have undesirable sedative effects on the central nervous systems (CNS), newer (second-generation) antihistamines have been developed to improve patients’ quality of life. However, there are few reports that directly compare the antihistaminic efficacy and impairment of psychomotor functions. We designed a double-blind, placebo controlled, crossover study to concurrently compare the clinical effectiveness of promethazine, a first-generation antihistamine, and fexofenadine and olopatadine, second-generation antihistamines, by measuring their potency as peripheral inhibitors of histamine-induced wheal and flare. Further, we investigated their sedative effects on the CNS using a battery of psychomotor tests. When single therapeutic doses of fexofenadine (60 mg), olopatadine (5 mg) and promethazine (25 mg) were given in a double-blind manner to 24 healthy volunteers, all antihistamines produced a significant reduction in the wheal and flare responses induced by histamine. In the comparison among antihistamines, olopatadine showed a rapid inhibitory effect compared with fexofenadine and promethazine, and had a potent effect compared with promethazine. In a battery of psychomotor assessments using critical flicker fusion, choice reaction time, compensatory tracking, rapid visual information processing and a line analogue rating scale as a subjective assessment of sedation, promethazine significantly impaired psychomotor function. Fexofenadine and olopatadine had no significant effect in any of the psychomotor tests. Promethazine, fexofenadine and olopatadine did not affect behavioral activity, as measured by wrist actigraphy. These results suggest that olopatadine at a therapeutic dose has greater antihistaminergic activity than promethazine, and olopatadine and fexofenadine did not cause cognitive or psychomotor impairment.
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Affiliation(s)
- Hiroyuki Kamei
- Department of Clinical Pharmacy Practice and Health Care Management, Meijo University, Nagoya, Japan
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20
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Yanai K, Zhang D, Tashiro M, Yoshikawa T, Naganuma F, Harada R, Nakamura T, Shibuya K, Okamura N. Positron emission tomography evaluation of sedative properties of antihistamines. Expert Opin Drug Saf 2011; 10:613-22. [DOI: 10.1517/14740338.2011.562889] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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21
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Kubo N, Senda M, Ohsumi Y, Sakamoto S, Matsumoto K, Tashiro M, Okamura N, Yanai K. Brain histamine H1 receptor occupancy of loratadine measured by positron emission topography: comparison of H1 receptor occupancy and proportional impairment ratio. Hum Psychopharmacol 2011; 26:133-9. [PMID: 21433074 DOI: 10.1002/hup.1184] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
AIMS We have evaluated the sedative properties of H1-antihistamines by using positron emission tomography (PET) and ¹¹C-doxepin. The purpose of the present study was to measure histamine H1 receptor occupancy (H1RO) of loratadine 10 mg in patients with allergic rhinitis and to compare this occupancy with that of d-chlorpheniramine 2 mg, a first-generation antihistamine. We also compared our PET findings with the proportional impairment ratio reported by McDonald et al. METHODS The H1RO of loratadine 10 mg and d-chlorpheniramine 2 mg were evaluated in human brains in a double-blind and crossover design using ¹¹C-doxepin PET. Eleven young male patients with allergic rhinitis were examined by PET following oral single administration of loratadine 10 mg and d-chlorpheniramine 2 mg. RESULTS Loratadine 10 mg occupied 11.7 ± 19.5% of histamine H1 receptors in the cortex, whereas d-chlorpheniramine 2 mg occupied 53.0 ± 33.2% in the same area, suggesting a non-sedating property of loratadine at a dose of 10 mg. The H1RO values of loratadine and d-chlorpheniramine as well as those of previous studies were found to be significantly proportional to the proportional impairment ratio (r = 0.899). CONCLUSION Measurement of H1RO is a sensitive and absolute method to characterize the non-sedating property of drugs with H1 antagonistic activity.
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Affiliation(s)
- Nobuo Kubo
- Department of Otolaryngology, Kansai Medical University, Osaka, Japan
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van Ruitenbeek P, Vermeeren A, Riedel WJ. Histamine H1 receptor antagonist cetirizine impairs working memory processing speed, but not episodic memory. Br J Pharmacol 2011; 161:456-66. [PMID: 20735428 DOI: 10.1111/j.1476-5381.2010.00907.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND AND PURPOSE The histaminergic neurotransmitter system is currently under investigation as a target for drug treatment of cognitive deficits in clinical disorders. The therapeutic potential of new drugs may initially be screened using a model of histaminergic dysfunction, for example, as associated with the use of centrally active antihistamines. Of the selective second generation antihistamines, cetirizine has been found to have central nervous system effects. The aim of the present study was to determine whether cetirizine can be used as a tool to model cognitive deficits associated with histaminergic hypofunction. EXPERIMENTAL APPROACH The study was conducted according to a three-way, double-blind, cross-over design. Treatments were single oral doses of cetirizine 10 and 20 mg and placebo. Effects on cognition were assessed using tests of word learning, memory scanning, vigilance, divided attention, tracking and visual information processing speed. KEY RESULTS Cetirizine 10 mg impaired tracking performance and both doses impaired memory scanning speed. None of the other measures indicated impaired performance. CONCLUSION AND IMPLICATIONS Cetirizine affects information processing speed, but these effects were not sufficient to serve as a model for cognitive deficits in clinical disorders.
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Affiliation(s)
- P van Ruitenbeek
- Department of Neuropsychology and Psychopharmacology, Faculty of Psychology and Neuroscience, Maastricht University, the Netherlands.
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Next-day residual sedative effect after nighttime administration of an over-the-counter antihistamine sleep aid, diphenhydramine, measured by positron emission tomography. J Clin Psychopharmacol 2010; 30:694-701. [PMID: 21105284 DOI: 10.1097/jcp.0b013e3181fa8526] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Antihistamines often are self-administered at night as over-the-counter (OTC) sleep aids, but their next-day residual sedative effect has never been evaluated using a reliable quantitative method such as positron emission tomography (PET). We performed a double-blind, placebo-controlled, crossover study in which we evaluated the residual effect the next day after nighttime administration of diphenhydramine, a commonly used OTC sleep aid, in terms of brain H₁ receptor occupancy (H₁RO) measured using ¹¹C-doxepin-PET. We also compared the results of diphenhydramine with those of bepotastine, a second-generation antihistamine. Eight healthy adult male subjects underwent PET measurement the morning (11:00) after random oral administration of diphenhydramine (50 mg), bepotastine (10 mg), or placebo the night before (23:00). Binding potential ratios and H₁ROs were calculated in different brain regions of interest such as the cingulate gyrus, frontotemporal cortex, and cerebellum. Subjective sleepiness and plasma drug concentration also were measured. Calculation of binding potential ratios revealed significantly lower values for diphenhydramine than for bepotastine or placebo in all regions of interest (P < 0.01). Cortical mean H₁RO after diphenhydramine treatment was 44.7% compared with 16.6% for bepotastine treatment (P < 0.01). Subjective sleepiness was not significantly different among the subjects treated with each test drug or the placebo. In conclusion, the next-day residual sedative effect after nighttime administration of the OTC sleep aid diphenhydramine was verified for the first time by direct PET measurement of H₁RO. Taking into account the possible hangover effect of OTC antihistamine sleep aids, care needs to be taken during their administration.
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Smith SM, Gums JG. Fexofenadine: biochemical, pharmacokinetic and pharmacodynamic properties and its unique role in allergic disorders. Expert Opin Drug Metab Toxicol 2010; 5:813-22. [PMID: 19545214 DOI: 10.1517/17425250903044967] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Fexofenadine is one of several second-generation H(1)-antihistamines approved for the treatment of various allergic disorders; however, it shows numerous unique properties that make it an optimal choice for many patients. OBJECTIVE To review the pharmacology, efficacy and safety of fexofenadine and the attributes differentiating it from other H(1)-antihistamines. METHODS We performed a literature search in PubMed/MEDLINE (1966 - March 2009) using the keywords fexofenadine, antihistamine, allergic rhinitis and chronic urticaria. We also reviewed data provided by the manufacturer in addition to reports from various governmental agencies. RESULTS/CONCLUSIONS Fexofenadine is devoid of sedative and anticholinergic effects and may offer equivalent or greater efficacy in treating allergic disorders compared with other currently available second-generation H(1)-antihistamines. In addition, fexofenadine may offer cost savings over other selected H(1)-antihistamines owing to its recent availability in generic form in the US.
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Affiliation(s)
- Steven M Smith
- University of Florida, Colleges of Pharmacy and Medicine, Departments of Pharmacotherapy & Translational Research and Community Health & Family Medicine, Gainesville, FL 32610-0486, USA.
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Tashiro M, Kato M, Miyake M, Watanuki S, Funaki Y, Ishikawa Y, Iwata R, Yanai K. Dose dependency of brain histamine H(1) receptor occupancy following oral administration of cetirizine hydrochloride measured using PET with [11C]doxepin. Hum Psychopharmacol 2009; 24:540-8. [PMID: 19697300 DOI: 10.1002/hup.1051] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
AIMS The strength of sedation due to antihistamines can be evaluated using positron emission tomography (PET). The purpose of the present study is to measure histamine H(1) receptor (H(1)R) occupancy following oral administration of cetirizine (10 and 20 mg) in order to examine dose dependency. METHODS Fifteen healthy male volunteers (age range, 20-35 years) were divided into 3 subgroups and were studied following single oral administration of cetirizine at 10 mg (n = 5) and 20 mg (n = 5) or hydroxyzine at 30 mg (n = 5) using PET with 11C-doxepin. Each subject was scanned also following the administration of placebo. Binding potential and H(1)RO values were calculated in the prefrontal and anterior cingulate cortices. Subjective sleepiness was also measured, and the correlation to H(1)RO was examined for each antihistamine. RESULTS The averaged H(1)ROs of cetirizine 10 mg, 20 mg, and hydroxyzine 30 mg in the prefrontal and cingulate cortices was 12.6%, 25.2%, and 67.6%, respectively. The H(1)RO of hydroxyzine 30 mg correlated well with subjective sleepiness (p < 0.001); however, those of cetirizine 10 and 20 mg showed no correlation with subjective sleepiness. CONCLUSION It was demonstrated that the brain penetration of orally administered cetirizine was dose-dependent. Cetirizine 10 mg, with its low H(1)RO and thus minimal sedation, could be more safely used than cetirizine 20 mg for the treatment of various allergic disorders.
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Affiliation(s)
- Manabu Tashiro
- Division of Cyclotron Nuclear Medicine, Tohoku University, Sendai, Miyagi, Japan.
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Yanai K, Okamura N, Tagawa M, Itoh M, Watanabe T. New findings in pharmacological effects induced by antihistamines: from PET studies to knock-out mice. Clin Exp Allergy 2009. [DOI: 10.1046/j.1365-2222.1999.00008.x-i1] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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27
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Selective histamine H1 antagonism: novel hypnotic and pharmacologic actions challenge classical notions of antihistamines. CNS Spectr 2008; 13:1027-38. [PMID: 19179941 DOI: 10.1017/s1092852900017089] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Numerous "antihistamines" as well as various psychotropic medications with antihistamine properties are widely utilized to treat insomnia. Over-the-counter sleep aids usually contain an antihistamine and various antidepressants and antipsychotics with antihistamine properties have sedative-hypnotic actions. Although widely used for the treatment of insomnia, many agents that block the histamine H1 receptor are also widely considered to have therapeutic limitations, including the development of next-day carryover sedation, as well as problems with chronic use, such as the development of tolerance to sedative-hypnotic actions and weight gain. Although these clinical actions are classically attributed to blockade of the H1 receptor, recent findings with H1 selective agents and H1 selective dosing of older agents are challenging these notions and suggest that some of the clinical limitations of current H1-blocking agents at their currently utilized doses could be attributable to other properties of these drugs, especially to their simultaneous actions on muscarinic, cholinergic, and adrenergic receptors. Selective H1 antagonism is emerging as a novel approach to the treatment of insomnia, without tolerance, weight gain, or the need for the restrictive prescription scheduling required of other hypnotics.
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Izumi N, Mizuguchi H, Umehara H, Ogino S, Fukui H. Evaluation of efficacy and sedative profiles of H(1) antihistamines by large-scale surveillance using the visual analogue scale (VAS). Allergol Int 2008; 57:257-63. [PMID: 18566547 DOI: 10.2332/allergolint.o-07-525] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2007] [Accepted: 01/31/2008] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND H(1) antihistamines are widely used as therapeutics for allergic diseases. Sedation is a well-known side effect of H(1) antihistamines and sometimes it is life-threatening for patients. Thus it is important to evaluate the sedative properties of H(1) antihistamines to avoid side effects. For this purpose, histamine H(1) receptor (H1R) occupancy and proportional impairment ratios (PIR) are now being used. However, it is not easy to obtain these parameters. Here, we sought to evaluate the sedative properties of H(1) antihistamines by means of a large-scale surveillance at health insurance pharmacies. METHODS The survey was conducted at 37 health insurance pharmacies. The therapeutic efficacy and the degree of sleepiness were quantified through a questionnaire using the visual analog scale (VAS) directly from 1742 patients who received H(1) antihistamines. RESULTS The degree of sleepiness caused by the first-generation antihistamines was significantly higher than that of the second-generation antihistamines. The high VAS score in case of efficacy was found in d-chlorpheniramine, olopatadine, and ebastine. Among the mean values of efficacy, all second-generation antihistamines except for loratadine, bepotastine, and mequitazine were significantly higher than that of clemastine. Regarding the degree of sleepiness, clemastine scored the highest VAS score, and significantly lower scores were obtained in all second-generation antihistamines. CONCLUSIONS The sedative properties of the H(1) antihistamines obtained from VAS analysis were very similar to those of H1R occupancy from positron emission tomography (PET) studies and PIR from meta-analysis. Our results indicate that large-scale surveillance using VAS might be useful to evaluate the profiles of H(1) antihistamines.
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Affiliation(s)
- Norimasa Izumi
- Department of Molecular Pharmacology, Institute of Health Biosciences, The University of Tokushima Graduate School, Japan
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Abstract
This article reviews the most common pharmacologic options in the treatment of sleep disorders in children. Despite the high prevalence of sleep disorders in children, there is a paucity of education and information available on the pharmacologic management of sleep disorders in children. The principles of sleep physiology and pathophysiology that help provide more rational pharmacologic management are discussed. Medications are typically not Food and Drug Administration (FDA) approved for the pediatric age range or for the specific sleep disorder. Medications have a role for insomnia, narcolepsy, parasomnias, and sleep-related movement disorders. The available choices of hypnotics are reviewed. Medications to increase alertness of narcoleptics and decrease cataplexy are discussed. The use of dopaminergic agents for Restless Legs Syndrome is reviewed. The potential use of medication in sleep apnea is also reviewed. Pharmacologic guidelines need to be developed specifically for sleep disorders in children. Ideally, these guidelines should be FDA approved for the specific sleep disorder and for the pediatric age range. The development of easy to swallow, chewable or liquid forms of these medications are needed. Training programs should play the lead role in enhancing pediatricians' knowledge of the pharmacologic treatment of sleep disorders in children.
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Tashiro M, Duan X, Kato M, Miyake M, Watanuki S, Ishikawa Y, Funaki Y, Iwata R, Itoh M, Yanai K. Brain histamine H1 receptor occupancy of orally administered antihistamines, bepotastine and diphenhydramine, measured by PET with 11C-doxepin. Br J Clin Pharmacol 2008; 65:811-21. [PMID: 18410464 DOI: 10.1111/j.1365-2125.2008.03143.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT 'Bepotastine besilate' is a novel second-generation antihistamine developed in Japan and its antiallergic effects have already been demonstrated by various studies. However, only a few clinical studies regarding its sedative property are available. In addition, histamine H(1) receptor occupancy (H(1)RO) of this new antihistamine has never been measured by positron emission tomography (PET). WHAT THIS STUDY ADDS This paper provides the first measurement result of cerebral H(1)RO of bepotastine besilate (approximately 15%) as determined by PET. This result is in accordance with the clinical classification of bepotastine as a second-generation antihistamine. In addition, the relationship between subjective sleepiness and cerebral H(1)RO of this second-generation antihistamine is demonstrated for the first time using a placebo-controlled crossover study design. AIMS Antihistamines are frequently used for treating various allergic diseases, but often induce sedation. The degree of sedation can be evaluated by measuring histamine H(1) receptor occupancy (H(1)RO) in the brain using positron emission tomography (PET). The aim was to measure H(1)RO of bepotastine, a new second-generation antihistamine, and to compare it with that of diphenhydramine. METHODS Eight healthy male volunteers (mean age +/- SD 24.4 +/- 3.3 years) were studied after single oral administration of bepotastine (10 mg), diphenhydramine (30 mg) or placebo, by PET imaging with (11)C-doxepin in a crossover study design. Binding potential ratio and H(1)ROs were calculated using placebo data and were compared between bepotastine and diphenhydramine in the anterior and posterior cingulate gyri (ACG and PCG, respectively), superior and inferior frontal cortices (SFC and IFC, respectively), orbitofrontal cortex (OFC), insular cortex (IC), lateral and medial temporal cortices (LTC and MTC, respectively), parietal cortex (PC), occipital cortex (OC) and sensorimotor cortex (SMC). Plasma concentration of each antihistamine was measured, and its correlation to H(1)RO was examined. RESULTS H(1)RO after bepotastine treatment was significantly lower than that after diphenhydramine treatment in all cortical regions (P < 0.001). Mean H(1)ROs of bepotastine and diphenhydramine were 14.7% and 56.4%, respectively. H(1)ROs of both bepotastine and diphenhydramine correlated to their respective drug plasma concentration (P < 0.001). CONCLUSION Oral bepotastine (10 mg), with its relatively low H(1)RO and thus minimal sedation, has the potential for use as a mildly or slightly sedative antihistamine in the treatment of various allergic disorders.
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Affiliation(s)
- Manabu Tashiro
- Division of Cyclotron Nuclear Medicine, Cyclotron and Radioisotope Centre, Tohoku University, Sendai, Miyagi, Japan.
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Tashiro M, Sakurada Y, Mochizuki H, Horikawa E, Maruyama M, Okamura N, Watanuki S, Arai H, Itoh M, Yanai K. Effects of a sedative antihistamine, D-chlorpheniramine, on regional cerebral perfusion and performance during simulated car driving. Hum Psychopharmacol 2008; 23:139-50. [PMID: 18181241 DOI: 10.1002/hup.909] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVES The sedative side effects of antihistamines have been recognized to be potentially dangerous in car driving, but the mechanism underlying these effects has not yet been elucidated to date. The aim of the present study is to examine regional cerebral blood flow (rCBF) responses during a simulated car-driving task following oral administration of D-chlorpheniramine using positron emission tomography (PET) and [15O]H2O, based on a single-blind cross-over study-design. METHODS Right-handed, healthy male volunteers (n = 14) drove a car in a simulated environment following oral administration of D-chlorpheniramine repetab 6 mg or placebo. Their rCBF was measured using PET with [15O]H2O in the following three conditions: (1) resting, (2) active driving, and (3) passive driving. All 'in-car' views during the simulated driving were videotaped and used for rating driving performance. RESULTS Performance evaluation revealed that the number of lane deviations significantly increased in the D-chlorpheniramine condition compared with the placebo condition (p < 0.01). Subjective sleepiness was not significantly different between the two drug conditions. The regions of diminished brain responses following D-chlorpheniramine treatment were detected in the parietal, temporal and visual cortices, and in the cerebellum. The regions of augmented rCBF responses were found in the orbitofrontal cortex and cerebellar vermis. CONCLUSION These results suggest that D-chlorpheniramine tends to suppress visuo-spatial cognition and visuo-motor coordinating functions rather than attention and motor functions during car driving.
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Affiliation(s)
- Manabu Tashiro
- Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Japan.
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Devillier P, Roche N, Faisy C. Clinical Pharmacokinetics and Pharmacodynamics of Desloratadine, Fexofenadine and Levocetirizine. Clin Pharmacokinet 2008; 47:217-30. [PMID: 18336052 DOI: 10.2165/00003088-200847040-00001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Philippe Devillier
- Laboratory of Pharmacology, UPRES EA 220, Université de Versailles Saint-Quentin, Hôpital Foch, Suresnes, France.
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Mimura N, Nagata Y, Kuwabara T, Kubo N, Fuse E. P-glycoprotein Limits the Brain Penetration of Olopatadine Hydrochloride, H1-Receptor Antagonist. Drug Metab Pharmacokinet 2008; 23:106-14. [DOI: 10.2133/dmpk.23.106] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Hou RH, Langley RW, Szabadi E, Bradshaw CM. Comparison of diphenhydramine and modafinil on arousal and autonomic functions in healthy volunteers. J Psychopharmacol 2007; 21:567-78. [PMID: 17092978 DOI: 10.1177/0269881106071022] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Arousal is regulated by the interplay between wakefulness- and sleep-promoting nuclei. Major wakefulness-promoting nuclei are the histaminergic tuberomamillary nucleus (TMN) of the hypothalamus and the noradrenergic locus coeruleus (LC) of the pons, which also play a role in autonomic regulation. First generation antihistamines, such as diphenhydramine, are likely to cause sedation by blocking excitatory H1 histamine receptors in the cerebral cortex, and the anti-narcolepsy drug modafinil may promote wakefulness by activating the locus coeruleus. We compared the effects of single doses of diphenhydramine (75 mg) and modafinil (200 mg) on arousal and autonomic functions in 16 healthy male volunteers, using a placebo-controlled, balanced, double-blind design. Arousal was assessed by critical flicker fusion frequency (CFFF), visual analogue scales (VAS) and pupillary fatigue waves (Pupillographic Sleepiness Test (PST)). Autonomic functions measured included resting pupil diameter, light and darkness reflex responses, blood pressure, heart rate and salivation. Data were analysed with ANOVA, with multiple comparisons. Diphenhydramine had sedative effects as shown by reductions in CFFF, VAS alertness ratings and increases of the indices of pupillary fatigue. Modafinil had alerting effects as indicated by reductions in the measures of pupillary fatigue. Comparison of pre-post medication changes in pupil diameter showed a decrease after diphenhydramine and an increase after modafinil. Diphenhydramine reduced salivation, and modafinil increased systolic blood pressure. In conclusion, diphenhydramine and modafinil evoked opposite effects on arousal and sympathetic functions, which are likely to reflect their interaction with the central histaminergic and noradrenergic systems. Hyposalivation by diphenhydramine is likely to be due to its additional anticholinergic property.
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Affiliation(s)
- R H Hou
- Psychopharmacology Section, Division of Psychiatry, University of Nottingham Medical School, Queen's Medical Centre, Nottingham, UK
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Walker S, Khan-Wasti S, Fletcher M, Cullinan P, Harris J, Sheikh A. Seasonal allergic rhinitis is associated with a detrimental effect on examination performance in United Kingdom teenagers: case-control study. J Allergy Clin Immunol 2007; 120:381-7. [PMID: 17560637 DOI: 10.1016/j.jaci.2007.03.034] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Revised: 03/23/2007] [Accepted: 03/26/2007] [Indexed: 10/23/2022]
Abstract
BACKGROUND Seasonal allergic rhinitis is common globally, and symptoms have been shown to impair learning ability in children in laboratory conditions. Critical examinations in children are often held in the summer during the peak grass pollen season. OBJECTIVE To investigate whether seasonal allergic rhinitis adversely impacts examination performance in United Kingdom teenagers. METHODS Case-control analysis of 1,834 students (age 15-17 years; 50% girls) sitting for national examinations. Cases were those who dropped 1 or more grades in any of 3 core subjects (mathematics, English, and science) between practice (winter) and final (summer) examinations; controls were those whose grades were either unchanged or improved. Associations between allergic rhinitis symptoms, clinician-diagnosed allergic rhinitis, and allergic rhinitis-related medication use, recorded on examination days immediately before the examination, were assessed using multilevel regression models. RESULTS Between 38% and 43% of students reported symptoms of seasonal allergic rhinitis on any 1 of the examination days. There were 662 cases (36% of students) and 1,172 controls. After adjustment, cases were significantly more likely than controls to have had allergic rhinitis symptoms during the examination period (odds ratio [OR], 1.4; 95% CI, 1.1-1.8; P = .002), to have taken any allergic rhinitis medication (OR, 1.4; 95% CI, 1.1-1.7; P = .01), or to have taken sedating antihistamines (OR, 1.7; 95% CI, 1.1-2.8; P = .03). CONCLUSION Current symptomatic allergic rhinitis and rhinitis medication use are associated with a significantly increased risk of unexpectedly dropping a grade in summer examinations. CLINICAL IMPLICATIONS This is the first time the relationship between symptomatic allergic rhinitis and poor examination performance has been demonstrated, which has significant implications for clinical practice.
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Obradovic T, Dobson GG, Shingaki T, Kungu T, Hidalgo IJ. Assessment of the First and Second Generation Antihistamines Brain Penetration and Role of P-Glycoprotein. Pharm Res 2006; 24:318-27. [PMID: 17180728 DOI: 10.1007/s11095-006-9149-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2006] [Accepted: 08/15/2006] [Indexed: 01/16/2023]
Abstract
PURPOSE The sedating effect of first generation H(1)-antihistamines has been associated with their ability to penetrate the blood-brain barrier (BBB) and lack of efflux by P-glycoprotein (Pgp). Second generation H(1)-antihistamines are relatively free of sedation and their limited brain penetration has been suggested to arise from Pgp-mediated efflux. The objective of this work was to evaluate the role of Pgp in brain penetration of first and second generation antihistamines. METHODS Potential of antihistamines to be Pgp substrates was tested in vitro using Madin Darby canine kidney cells transfected with human Pgp. The role of Pgp in limiting brain penetration of antihistamines was tested by using the in situ brain perfusion technique. RESULTS Majority of antihistamines were Pgp substrates in vitro. Following in situ brain perfusion, the first generation antihistamines substantially penetrated into rat brain independently from Pgp function. The second generation antihistamines terfenadine and loratadine, achieved substantial brain penetration, which was further enhanced by Pgp inhibition by cyclosporin A (CSA). In contrast, fexofenadine and cetirizine, penetrated brain poorly regardless of CSA administration. CONCLUSIONS Antihistamines greatly differ in their ability to cross the BBB as well as in the role of Pgp in limiting their transport into the CNS in vivo.
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Affiliation(s)
- Tanja Obradovic
- Absorption Systems, Oaklands Corporate Center, 440 Creamery Way, Suite 300, Exton, Pennslyvania 19341-2554, USA.
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Dai H, Kaneko K, Kato H, Fujii S, Jing Y, Xu A, Sakurai E, Kato M, Okamura N, Kuramasu A, Yanai K. Selective cognitive dysfunction in mice lacking histamine H1 and H2 receptors. Neurosci Res 2006; 57:306-13. [PMID: 17145090 DOI: 10.1016/j.neures.2006.10.020] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2006] [Revised: 10/27/2006] [Accepted: 10/31/2006] [Indexed: 10/23/2022]
Abstract
Previous pharmacological experiments provide conflicting findings that describe both facilitatory and inhibitory effects of neuronal histamine on learning and memory. Here, we examined learning and memory and synaptic plasticity in mice with a null mutation of gene coding histamine H1 or H2 receptor in order to clarify the role of these receptors in learning and memory processes. Learning and memory were evaluated by several behavioral tasks including object recognition, Barnes maze and fear conditioning. These behavioral tasks are highly dependent on the function of prefrontal cortex, hippocampus or amygdala. Object recognition and Barnes maze performance were significantly impaired in both H1 receptor gene knockout (H1KO) and H2 receptor gene knockout (H2KO) mice when compared to the respective wild-type (WT) mice. Conversely, both H1KO and H2KO mice showed better auditory and contextual freezing acquisition than their respective WT mice. Furthermore, we also examined long-term potentiation (LTP) in the CA1 area of hippocampus in H1KO and H2KO mice and their respective WT mice. LTP in the CA1 area of hippocampus was significantly reduced in both H1KO and H2KO mice when compared with their respective WT mice. In conclusion, our results demonstrate that both H1 and H2 receptors are involved in learning and memory processes for which the frontal cortex, amygdala and hippocampus interact.
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Affiliation(s)
- Hongmei Dai
- Department of Pharmacology, Tohoku University School of Medicine, 2-1 Seiryo-Machi, Sendai, Japan
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Yanai K, Tashiro M. The physiological and pathophysiological roles of neuronal histamine: an insight from human positron emission tomography studies. Pharmacol Ther 2006; 113:1-15. [PMID: 16890992 DOI: 10.1016/j.pharmthera.2006.06.008] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2006] [Accepted: 06/12/2006] [Indexed: 01/27/2023]
Abstract
Histamine neurons are exclusively located in the posterior hypothalamus, and project their fibers to almost all regions of the human brain. Although a significant amount of research has been done to clarify the functions of the histaminergic neuron system in animals, a few studies have been reported on the roles of this system in the human brain. In past studies, we have been able to clarify some of the functions of histamine neurons using different methods, such as histamine-related gene knockout mice or human positron emission tomography (PET). The histaminergic neuron system is known to modulate wakefulness, the sleep-wake cycle, appetite control, learning, memory and emotion. Accordingly we have proposed that histamine neurons have a dual effect on the CNS, with both stimulatory and suppressive actions. As a stimulator, neuronal histamine is one of the most important systems that stimulate and maintain wakefulness. Brain histamine also functions as a suppressor in bioprotection against various noxious and unfavorable stimuli of convulsion, drug sensitization, denervation supersensitivity, ischemic lesions and stress susceptibility. This review summarizes our works on the functions of histamine neurons using human PET studies, including the development of radiolabeled tracers for histamine H1 receptors (H1R: (11)C-doxepin and (11)C-pyrilamine), PET measurements of H1R in depression, schizophrenia, and Alzheimer's disease (AD), and studies on the sedative effects of antihistamines using H(2)(15)O and H1R occupancy in the human brain. These molecular and functional PET studies in humans are useful for drug development in this millennium.
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Affiliation(s)
- Kazuhiko Yanai
- Department of Pharmacology, Tohoku University School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai, Miyagi 980-8575, Japan.
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Tashiro M, Mochizuki H, Sakurada Y, Ishii K, Oda K, Kimura Y, Sasaki T, Ishiwata K, Yanai K. Brain histamine H receptor occupancy of orally administered antihistamines measured by positron emission tomography with (11)C-doxepin in a placebo-controlled crossover study design in healthy subjects: a comparison of olopatadine and ketotifen. Br J Clin Pharmacol 2006; 61:16-26. [PMID: 16390347 PMCID: PMC1884984 DOI: 10.1111/j.1365-2125.2005.02514.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
AIMS The strength of sedation due to antihistamines can be evaluated by using positron emission tomography (PET). The purpose of the present study is to measure histamine H(1) receptor (H(1)R) occupancy due to olopatadine, a new second-generation antihistamine and to compare it with that of ketotifen. METHODS Eight healthy males (mean age 23.5 years-old) were studied following single oral administration of olopatadine 5 mg or ketotifen 1 mg using PET with (11)C-doxepin in a placebo-controlled crossover study design. Binding potential ratio and H(1)R occupancy were calculated and were compared between olopatadine and ketotifen in the medial prefrontal (MPFC), dorsolateral prefrontal (DLPFC), anterior cingulate (ACC), insular (IC), temporal (TC), parietal (PC), occipital cortices (OC). Plasma drug concentration was measured, and correlation of AUC to H(1)R occupancy was examined. RESULTS H(1)R occupancy after olopatadine treatment was significantly lower than that after ketotifen treatment in the all cortical regions (P < 0.001). Mean H(1)R occupancies for olopatadine and ketotifen were, respectively: MPFC, 16.7 vs. 77.7; DLPFC, 14.1 vs. 85.9; ACC, 14.7 vs. 76.1; IC, 12.8 vs. 69.7; TC, 12.5 vs. 66.5; PC, 13.9 vs. 65.8; and OC, 19.5 vs. 60.6. Overall cortical mean H(1)R occupancy of olopatadine and ketotifen were 15% and 72%, respectively. H(1)R occupancy of both drugs correlated well with their respective drug plasma concentrations (P < 0.001). CONCLUSION It is suggested that 5 mg oral olopatadine, with its low H(1)R occupancy and thus minimal sedation, could safely be used an antiallergic treatment for various allergic disorders. Abbreviations histamine H(1) receptor (H(1)R), histamine H(1) receptor occupancy (H(1)RO), dopamine D(2) receptor (D(2)R), positron emission tomography (PET), blood-brain barrier (BBB), binding potential ratio (BPR), distribution volume (DV).
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Affiliation(s)
- Manabu Tashiro
- Department of Pharmacology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
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Morgan MM, Khan DA, Nathan RA. Treatment for allergic rhinitis and chronic idiopathic urticaria: focus on oral antihistamines. Ann Pharmacother 2005; 39:2056-64. [PMID: 16278258 DOI: 10.1345/aph.1e638] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To review the efficacy and safety of first- and newer-generation antihistamines for the management of allergic rhinitis and chronic idiopathic urticaria (CIU), with a focus on management in the pharmacy. DATA SOURCES A literature review was performed using MEDLINE (1966-October 2005), with no time or language restrictions. Key words or phrases used were histamine, antihistamine(s), first- and second-generation, allergic rhinitis, chronic idiopathic urticaria, quality of life, impairment, sedation, cost-effectiveness, astemizole, cetirizine, desloratadine, diphenhydramine, fexofenadine, loratadine, hydroxyzine, ketotifen, and mizolastine. Additional references were found in the bibliographies of the articles cited. STUDY SELECTION AND DATA EXTRACTION Clinical trials and other experimental studies of the use of antihistamines for the management of allergic rhinitis and CIU were selected. Review papers and guidelines were also included. DATA SYNTHESIS First-generation antihistamines are effective at ameliorating the symptoms of allergic rhinitis and CIU; however, they are associated with adverse effects due to a lack of selectivity for the histamine H(1)-receptor and an ability to bind to cerebral H(1)-receptors. Newer-generation agents, in general, possess high H(1)-receptor selectivity and a low tendency to cross the blood-brain barrier, while maintaining efficacy. In general, safety at elevated doses has been demonstrated for the newer antihistamines, although higher rates of sedation and impairment have been reported with increasing doses for some agents. CONCLUSIONS Pharmacists can play an important role in the management of allergic rhinitis and CIU by considering the relative advantages of newer-generation agents when reviewing treatment options.
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Suzuki A, Tashiro M, Kimura Y, Mochizuki H, Ishii K, Watabe H, Yanai K, Ishiwata K, Ishii K. Use of reference tissue models for quantification of histamine H1 receptors in human brain by using positron emission tomography and [11C]doxepin. Ann Nucl Med 2005; 19:425-33. [PMID: 16248378 DOI: 10.1007/bf02985569] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The aim of the present study is to evaluate the validity of the simplified reference tissue model (SRTM) and of Logan graphical analysis with reference tissue (LGAR) for quantification of histamine H1 receptors (H1Rs) by using positron emission tomography (PET) with [11C]doxepin. These model-based analytic methods (SRTM and LGAR) are compared to Logan graphical analysis (LGA) and to the one-tissue model (1TM), using complete datasets obtained from 5 healthy volunteers. Since HIR concentration in the cerebellum can be regarded as negligibly small, the cerebellum was selected as the reference tissue in the present study. The comparison of binding potential (BP) values estimated by LGAR and 1TM showed good agreement; on the other hand, SRTM turned out to be unstable concerning parameter estimation in several regions of the brain. By including the results of noise analysis, LGAR became a reliable method for parameter estimation of [11C]doxepin data in the cortical regions.
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Affiliation(s)
- Atsuro Suzuki
- Department of Quantum Science and Energy Engineering, Tohoku University, Sendai, Japan
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Greaves MW. Antihistamines in Dermatology. Skin Pharmacol Physiol 2005; 18:220-9. [PMID: 16015020 DOI: 10.1159/000086667] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2005] [Accepted: 03/11/2005] [Indexed: 11/19/2022]
Abstract
Along with antibiotics, antihistamines are the most widely used systemic drugs in dermatology. This is attributable to the major role played by histamine in common diseases such as urticaria and atopic eczema. Of the currently recognised four subtypes of G protein-coupled histamine receptors, only the H1 and H2 subtypes have been positively identified in human skin. Traditionally believed to be competitive antagonists of histamine, H1 and H2 antihistamines are now considered to behave as inverse agonists. By consensus, H1 antihistamines are classified as 'first generation' (associated with troublesome side-effects including somnolence, anti-adrenergic and atropine-like actions) and 'second-generation' compounds (in which these side-effects are reduced or absent). The main indications for H1 antihistamines in skin are suppression of pruritus in urticaria and atopic eczema, both of which are associated with increased mast cell numbers and tissue histamine levels. However the evidence basis for use in atopic eczema is ambiguous and controversial, even though these drugs are widely used in practice. Currently, significant side-effects are mainly confined to the first-generation compounds and are especially troublesome in the elderly. Psychomotor impairment may persist throughout the day following administration. Anti-cholinergic and anti-alpha-adrenergic blockade and cardiotoxicity (torsade de pointes) may also occur with first-generation antihistamines. Two early low-sedation second-generation antihistamines caused arrhythmias in a small number of patients but these compounds have now been withdrawn. Generally, the second-generation H1 antihistamines are well tolerated.
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Okuda T, Ito Y, Nakagawa N, Hishinuma T, Tsukamoto H, Iwabuchi K, Watanabe T, Kitaichi K, Goto J, Yanai K. Drug interaction between methamphetamine and antihistamines: behavioral changes and tissue concentrations of methamphetamine in rats. Eur J Pharmacol 2005; 505:135-44. [PMID: 15556146 DOI: 10.1016/j.ejphar.2004.10.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Revised: 09/10/2004] [Accepted: 10/12/2004] [Indexed: 11/23/2022]
Abstract
Methamphetamine is a psychomotor stimulant, whereas first generation antihistamines cause sedation. Several studies have demonstrated that first generation antihistamines potentiate methamphetamine-induced psychomotor activation and two possible mechanisms have been postulated. One is blockage of the central histaminergic neuron system and the other is inhibition of dopamine reuptake. However, the exact mechanism is still controversial. In this study, we examined in behavioral tests the effects of selected antihistamines on methamphetamine-induced psychomotor activation in rats, and measured plasma and brain tissue concentrations of methamphetamine. We found that some antihistamines significantly potentiate methamphetamine-induced psychomotor activation in rats and that plasma and brain tissue concentrations of methamphetamine in rats treated with methamphetamine in combination with D-chlorpheniramine were markedly higher than those in rats treated with methamphetamine alone. These results suggest that the potentiating effects of antihistamines are due to not only central effects but also the alteration of the pharmacokinetics of methamphetamine.
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Affiliation(s)
- Tomohiro Okuda
- Department of Pharmacology, Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan
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Kubo N. [Social requirement of the antihistamines for Japanese pollinosis]. Nihon Yakurigaku Zasshi 2005; 125:279-84. [PMID: 15997164 DOI: 10.1254/fpj.125.279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
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Tashiro M, Sakurada Y, Iwabuchi K, Mochizuki H, Kato M, Aoki M, Funaki Y, Itoh M, Iwata R, Wong DF, Yanai K. Central effects of fexofenadine and cetirizine: measurement of psychomotor performance, subjective sleepiness, and brain histamine H1-receptor occupancy using 11C-doxepin positron emission tomography. J Clin Pharmacol 2005; 44:890-900. [PMID: 15286093 DOI: 10.1177/0091270004267590] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Histamine H1-receptor (H1R) antagonists, or antihistamines, often induce sedative side effects when used for the treatment of allergic disorders. This study compared the sedative profiles of the second-generation antihistamines, fexofenadine and cetirizine, using 3 different criteria: subjective sleepiness evaluated by the Stanford Sleepiness Scale, objective psychomotor tests (simple and choice reaction time tests and visual discrimination tests at 4 different exposure durations), and measurement of histamine H1-receptor occupancy (H1RO) in the brain. Subjective sleepiness and psychomotor performance were measured in 20 healthy Japanese volunteers at baseline and 90 min after administration of fexofenadine 120 mg or cetirizine 20 mg in a double-blind, placebo-controlled crossover study. Hydroxyzine 30 mg was included as a positive control. H1RO was measured using positron emission tomography (PET) with (11)C-doxepin in 12 of the 20 subjects, and a further 11 volunteers were recruited to act as controls. In psychomotor tests, fexofenadine was not significantly different from placebo and significantly less impairing than cetirizine on some tasks, as well as significantly less impairing than hydroxyzine on all tasks. For subjective sleepiness, fexofenadine was not significantly different from placebo, whereas cetirizine showed a trend toward increased sleepiness compared with fexofenadine and placebo. H1RO was negligible with fexofenadine (-0.1%) but moderately high with cetirizine (26.0%). In conclusion, fexofenadine 120 mg is distinguishable from cetirizine 20 mg, as assessed by H1RO and psychomotor testing.
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Affiliation(s)
- Manabu Tashiro
- Department of Pharmacology, Tohoku University School of Medicine, 2-1 Seiryo-cho, Aoba-ku, Sendai, Miyagi 980-8575, Japan
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46
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Iwabuchi K, Ito C, Tashiro M, Kato M, Kano M, Itoh M, Iwata R, Matsuoka H, Sato M, Yanai K. Histamine H1 receptors in schizophrenic patients measured by positron emission tomography. Eur Neuropsychopharmacol 2005; 15:185-91. [PMID: 15695063 DOI: 10.1016/j.euroneuro.2004.10.001] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2004] [Revised: 10/07/2004] [Accepted: 10/08/2004] [Indexed: 10/26/2022]
Abstract
Increasing evidence has shown that the histaminergic neuron system is implicated in the pathophysiology of schizophrenia. The aim of this study was to compare the distribution of histamine H1 receptors between schizophrenics and normal human subjects in vivo using positron emission tomography (PET). H1 receptor binding was measured in 10 normal subjects and 10 medicated schizophrenic patients by PET and [11C] doxepin, a radioligand for the H1 receptor. The binding potential (BP=Bmax/K(D)) of [11C] doxepin for available brain H1 receptors was calculated by a graphical analysis on voxel-by-voxel basis and compared between schizophrenics and normal subjects using the regions of interest (ROIs) and the statistical parametrical mapping (SPM99). BP values for H1 receptors in the frontal and prefrontal cortices and the cingulate gyrus were significantly lower among the schizophrenic patients than among the control subjects. On the contrary, there were no areas of the brain where H1 receptors were significantly higher among the schizophrenic patients than the control subjects. The results of our study suggest that the central histaminergic neuron system could be involved in the pathophysiology of schizophrenia, although further studies are needed to confirm this hypothesis.
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Affiliation(s)
- Kentaro Iwabuchi
- Department of Psychiatry, Tohoku University School of Medicine, Sendai 980-8575, Japan
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Sarashina A, Tatami S, Yamamura N, Tsuda Y, Igarashi T. Population pharmacokinetics of epinastine, a histamine H1 receptor antagonist, in adults and children. Br J Clin Pharmacol 2005; 59:43-53. [PMID: 15606439 PMCID: PMC1884954 DOI: 10.1111/j.1365-2125.2005.2250] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
AIMS Our objective was to develop a population pharmacokinetic (PPK) model for epinastine, a histamine H(1) receptor antagonist, in adults and children and to obtain pharmacokinetic information to support dosing recommendations in children. METHODS A total of 1510 plasma samples were collected from 62 healthy adult volunteers and 62 paediatric atopic dermatitis patients. The data were analysed using the NONMEM program according to a two-compartment model with first-order absorption. In addition, the final PPK model was evaluated by means of bootstrapping resampling. RESULTS The oral clearance (CL/F) was found to be associated with body weight, formulation and food status. The volume of distribution of the central compartment (V(1)/F) was related to body weight and food status. An absorption lag time was apparent in fed subjects. On the other hand, other covariates (formulation on V(1)/F, volume of distribution of the peripheral compartment (V(2)/F), first-order absorption rate constant (Ka) and absorption lag time (ALAG); food status on V(2)/F and Ka; body weight on V(2)/F) were not statistically significant. No effect of age on CL/F, V(1)/F or V(2)/F was found. The mean parameter estimates obtained with an additional 200 bootstrap replicates of data were within 90-117% of those obtained with the original data set. These results suggest that the pharmacokinetics of epinastine are similar in adults and in children, except for the effect of the difference of body weight. The result of the application of the PPK model to the clinical trial in paediatric patients, in which dosage was determined based on the body weight (from 14 kg to less than 24 kg; 10 mg dose, 24 kg or more; 20 mg dose), showed that the C(max) and AUC (25.6 +/- 6.9 ng ml(-1) and 246.8 +/- 68.2 ng h ml(-1)) were almost same levels with those of adults after administration of 20 mg (26.9 +/- 9.1 ng ml(-1) and 281.6 +/- 90.5 ng h ml(-1)). CONCLUSIONS A PPK model for epinastine was established and further evaluation by bootstrapping indicated that this model is stable. The model shows that, if dosage is adjusted based on the body weight, the epinastine exposure in paediatric patients is similar to that in adults.
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Affiliation(s)
- A Sarashina
- Department of Drug Metabolism and Pharmacokinetics, Kawanishi Pharma Research Institute, Nippon Boehringer Ingelheim Co. Ltd., Kawanishi 666-0193, Japan
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Kano M, Fukudo S, Tashiro A, Utsumi A, Tamura D, Itoh M, Iwata R, Tashiro M, Mochizuki H, Funaki Y, Kato M, Hongo M, Yanai K. Decreased histamine H1 receptor binding in the brain of depressed patients. Eur J Neurosci 2004; 20:803-10. [PMID: 15255990 DOI: 10.1111/j.1460-9568.2004.03540.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The central histaminergic neuron system modulates the wakefulness, sleep-awake cycle, appetite control, learning and memory, and emotion. Previous studies have reported changes in neuronal histamine release and its metabolism under stress conditions in the mammalian brain. In this study, we examined, using positron emission tomography (PET) and [(11)C]-doxepin, whether the histaminergic neuron system is involved in human depression. Cerebral histamine H1 receptor (H(1)R) binding was measured in 10 patients with major depression and in 10 normal age-matched subjects using PET and [(11)C]-doxepin. Data were calculated by a graphical analysis on voxel-by-voxel and ROI (region of interests) basis. Binding potential (BP) values for [(11)C]-doxepin binding in the frontal and prefrontal cortices, and cingulate gyrus were significantly lower in the depressed patients than those in the normal control subjects. There was no area of the brain where [(11)C]-doxepin binding was significantly higher in the depressed patients than in the controls. ROI-based analysis also revealed that BP values for [(11)C]-doxepin binding in the frontal cortex and cingulate gyrus decreased in proportion to self-rating depressive scales scores. The results of this study demonstrate that depressed patients have decreased brain H(1)R binding and that this decrease correlates with the severity of depression symptoms. It is therefore suggested that the histaminergic neuron system plays an important role in the pathophysiology of depression and that its modulation may prove to be useful in the treatment of depression.
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Affiliation(s)
- Michiko Kano
- Department of Behavioural Medicine, Tohoku University School of Medicine, Sendai 980-8575, Japan
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Ishiwata K, Kawamura K, Wang WF, Tsukada H, Harada N, Mochizuki H, Kimura Y, Ishii K, Iwata R, Yanai K. Evaluation of in vivo selective binding of [11C]doxepin to histamine H1 receptors in five animal species. Nucl Med Biol 2004; 31:493-502. [PMID: 15093820 DOI: 10.1016/j.nucmedbio.2003.11.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2003] [Revised: 11/18/2003] [Accepted: 11/27/2003] [Indexed: 10/26/2022]
Abstract
The specific binding of [(11)C]doxepin, which has been used as a radioligand for mapping histamine H(1) receptors in human brain by positron emission tomography, was evaluated in five animal species. In mice the [(11)C]doxepin uptake was reduced by treatment with cold doxepin and two H(1) receptor antagonists, but not with H(2)/H(3) antagonists. The specific binding evaluated with treatment with (+)-chlorpheniramine (H(1) antagonist) was in the range of 10-30% in mouse, rat, rabbit, and monkey, but was not detected in guinea pig.
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Affiliation(s)
- Kiichi Ishiwata
- Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, 1-1 Naka-cho, Itabashi-ku, Tokyo 173-0022, Japan.
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Ng KH, Chong D, Wong CK, Ong HT, Lee CY, Lee BW, Shek LPC. Central nervous system side effects of first- and second-generation antihistamines in school children with perennial allergic rhinitis: a randomized, double-blind, placebo-controlled comparative study. Pediatrics 2004; 113:e116-21. [PMID: 14754980 DOI: 10.1542/peds.113.2.e116] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE Allergic rhinitis is common and on the rise. Antihistamines are the mainstay of treatment and are the most commonly prescribed drugs in Singapore. Treatment-related sedation and its effect on cognition are a major concern. First- and second-generation antihistamines show varying degrees of sedation, but to date, objective studies in children are lacking. The objective of this study was to assess the sedating effect of cetirizine (second-generation antihistamine) and chlorpheniramine (first-generation antihistamine) compared with placebo using an objective neurophysiological test. METHODS This was a prospective, double-blind, placebo-controlled, randomized, single-dose, 3-way crossover study. Twenty-four children aged 7 to 14 years with allergic rhinitis completed the study. All children were randomly allocated to medication sequences and received 3 different drugs on 3 different days, at least 1 week apart. The P300 event-related potential was used as an objective test of sedation. Subjective assessment was by a visual analog scale. RESULTS Chlorpheniramine and cetirizine increased P300 latency when compared with baseline. No significant increase was obtained with placebo. The significant increase in P300 latency was not accompanied by significant change in subjective somnolence as measured by the visual analog scale. CONCLUSION We have shown that cetirizine has sedative properties in children. The lack of correlation between P300 latency and the visual analog scale indicates that sedation induced by these drugs may not be subjectively noted.
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Affiliation(s)
- Kar Hui Ng
- Department of Paediatrics, National University of Singapore, Singapore
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