Escitalopram : a review of its use in the management of major depressive and anxiety disorders

Selective serotonin reuptake inhibitors regulate the interrelation between 5-HT and inflammation after myocardial infarction

BACKGROUND

Acute myocardial infarction (AMI) is a main cause of death all around the world. There is a close relationship between myocardial infarction (MI) and depression. MI patients with untreated depression had higher mortality than those without depression. Therefore, this study aimed to explore the effect of escitalopram in treating a model under MI and unpredictable chronic mild stress (UCMS).

METHODS

Male C57BL/6J mice were treated with sham surgery, or MI surgery, or UCMS, or escitalopram (ES) for a consecutive two weeks. And the mice were divided into Sham group, MI group, MI + UCMS group, MI + UCMS + ES group (n = 8 in each group). After treatment, the mice went through open field test for anxiety behavior, sucrose preference test for depressive behavior. After sacrificed, the blood, heart, hippocampus, and cortex were collected.

RESULTS

The escitalopram badly increased the area of cardiac fibrosis size. The sucrose preference test demonstrated that escitalopram treatment showed significant effect in improving depressive behaviors of mice under MI + UCMS. The potential mechanism involved the interrelation between 5-HT system and inflammation. MI significantly affected the level of cardiac SERT. Both UCMS and ES significantly affected the level of cortex TNF-α. UCMS significantly affected the level of cardiac IL-33. In the hippocampus tissue, TNF-α was positively correlated with SERT, and IL-10 was positively correlated with SERT. In the cortex tissue, IL-33 was positively correlated with 5-HT4R, and sST2 was positively correlated with 5-HT.

CONCLUSIONS

Two-week escitalopram treatment might worsen myocardial infarction. But escitalopram could benefit depressive behaviors, which may be related with the interrelationship between the 5-HT system and inflammatory factors in the brain.

Rise of escitalopram and the fall of citalopram

Introduction

Citalopram and escitalopram are among the most used medications and are key treatments for many psychiatric disorders. Previous findings suggest citalopram and escitalopram prescription rates are changing because of the patent for citalopram ending as opposed to evidence of a clear therapeutic advantage, which is called evergreening. This retrospective study focuses on characterizing the chronologic and geographic variation in the use of citalopram and escitalopram among US Medicaid and Medicare patients. We hypothesized that prescription rates of citalopram will decrease with a concurrent increase in escitalopram, consistent with evergreening.

Methods

Citalopram and escitalopram prescription rates and costs per state were obtained from the Medicaid State Drug Utilization Database and Medicare Provider Utilization and Payment Data. Annual prescription rates outside a 95% confidence interval were considered significantly different from the average.

Results

Overall, a decreasing trend for citalopram and an increasing trend for escitalopram prescription rates were noted in both Medicare and Medicaid patients. Cost differences between generic and brand were noted for both drugs, with generic forms being cheaper compared to the brand-name version.

Discussion

Despite limited evidence suggesting that citalopram and escitalopram have any meaningful differences in therapeutic or adverse effects, there exists a noticeable decline in the use of citalopram that cooccurred with an increase in escitalopram prescribing, consistent with our hypothesis. Moreover, among these general pharmacoepidemiologic trends exists significant geographic variability. There was disproportionate spending (relative to their use) on the brand versions of these medicines compared to their generic forms.

Escitalopram's inflammatory effect on the mammalian macrophages and its intracellular mechanism of action

The majority of patients with depression are treated with antidepressant drugs that are in the serotonin reuptake inhibitor (SSRI) group. Different studies have been conducted on the effect of treatment with antidepressants on the level of pro-inflammatory cytokines. There have been studies on the effects of escitalopram, an SSRI group antidepressant, on the pro-inflammatory cytokine levels both in vivo and in vitro. The results of these studies do not overlap and therefore the escitalopram's effect on the immune system should be studied in more depth. In this study, we aimed to examine, in detail, the cytokine production amount by escitalopram treatment of the J774.2 macrophage cells and its intracellular mechanism of action by examining the PI3K and p38 pathways. As a result of our study, we observed that Escitalopram caused a significant increase in TNF-α, IL-6, and GM-CSF levels in mammalian macrophage cells, but did not induce IL-12p40 production. We observed that the p38 and PI3K pathways play a role in inflammation in the presence of Escitalopram.

Investigation of the degradation and in-situ amorphization of the enantiomeric drug escitalopram oxalate during Fused Deposition Modeling (FDM) 3D printing

Hot-melt extrusion (HME) and subsequent FDM 3D printing offer great potential opportunities in the formulation development and production of customized oral dosage forms with poorly soluble drugs. However, thermal stress within these processes can be challenging for thermo-sensitive drugs. In this work, three different formulations were prepared to investigate the degradation and the solid state of the thermo-sensitive and poorly soluble drug escitalopram oxalate (ESC-OX) during the two heat-intensive processes HME and FDM 3D printing. For this purpose, hydroxypropyl methyl cellulose (HPMC) and basic butylated methacrylate copolymer (bPMMA) were chosen as polymers. DSC and XRD measurements revealed that ESC-OX is amorphous in the HPMC based formulations in both, extrudates and 3D printed tablets. In contrast, in-situ amorphization of the drug from crystalline state in bPMMA filaments was observed during FDM 3D printing. With regard to the content, it was found that degradation of ESC-OX in extrudates with bPMMA could be avoided and in 3D printed tablets almost fully reduced. Furthermore, a possible conversion into the R-enantiomer in the formulation with bPMMA could be excluded using a chiral column. Compared to the commercial product Cipralex®, drug release from extrudates and tablets with bPMMA was slower but still qualified as immediate drug release.

Early prenatal and late prenatal escitalopram exposure differentially impacts behavioral flexibility and anxiety-related behaviors in adulthood

Selective serotonin reuptake inhibitors (SSRIs) are medications commonly used by pregnant women. While SSRIs have been considered safe during pregnancy, there is limited understanding of the long-term consequences of prenatal SSRI exposure on adult behavioral processes. Recent human studies have demonstrated prenatal exposure to some SSRIs in humans may increase susceptibility to autism spectrum disorder (ASD) and developmental delays. While escitalopram is one of the most effective antidepressants, it is also one of the newer available SSRIs, resulting in less information on its safety profile during pregnancy. The current study administered escitalopram (0 or 10 mg/kg, s.c.) to nulliparous female Long-Evans rats for the first (G1-10) or last half (G11-20) of the gestational period. Young adult male and female offspring were subsequently tested on a battery of behavioral tasks consisting of probabilistic reversal learning task, open field conflict, marble burying and social approach tasks. Results demonstrate that escitalopram exposure during the first half of pregnancy resulted in reduced anxiety-like behavior (disinhibition) on the modified open field and enhanced flexibility on the probabilistic reversal learning task. Exposure to escitalopram later in pregnancy resulted in an increase in marble burying behavior, but no differences were found with the other measures. These results suggest that exposure to escitalopram during the first half of prenatal development can have long lasting changes on adult behavior demonstrating better behavioral flexibility and lower anxiety-like behavior compared to non-exposed controls.

The inhibitory effect of escitalopram on mouse detrusor contractility: The role of L-type calcium channels

Selective serotonin reuptake inhibitors (SSRIs) are associated with urinary problems attributed to their central effects. ESC is a preferred SSRI and several case reports described that ESC is related to urinary retention. However, the direct effect of ESC on detrusor contractility is still not completely elucidated. Thus, we investigated the effect of ESC on detrusor contractility and mechanism(s) of its action in isolated mouse detrusor strips. Molecular docking and measurement of intracellular calcium were performed to determine the possible calcium channel blocking effect of ESC. The contractile responses to carbachol (CCh), KCl and electrical field stimulation of detrusor strips were significantly abolished by ESC (10 or 100 μM). ESC relaxed KCl-precontracted detrusor strips concentration-dependently, which was not affected by tetraethylammonium, glibenclamide, 4-aminopyridine, propranolol, L-NAME or methylene blue. ESC (10 or 100 μM) reduced both the CaCl₂- and CCh-induced contractions under calcium-free conditions, indicating the role of calcium-involved mechanisms in ESC-mediated relaxation. Furthermore, ESC significantly decreased Bay K8644-induced contraction and the cytosolic calcium level in fura-2-loaded A7r5 cells. Molecular docking study also revealed the potential of ESC to bind L-type calcium (Ca_v1) channels. Our results demonstrate that ESC inhibits detrusor contractility via blocking Ca_v1 channels, which provides evidence for the direct effect of ESC on detrusor contractility and its mechanism.

A Review of Clinical Studies Assessing the Therapeutic Efficacy of Escitalopram: A Step Towards Development

BACKGROUND

Major depression is a debilitating, sometimes fatal disorder, deteriorating the quality of life and well-being. Escitalopram showed highly selective and dose-dependent inhibitory activity on human serotonin transport. Selective serotonin reuptake inhibitors (SSRIs) are the first-line drugs to manage major depressive disorder (MDD).

OBJECTIVE

The objective of this study is to explore the therapeutic potential of escitalopram, a clinically approved drug to manage MDD and panic disorders.

METHODS

It emphasizes comparative and clinical trial studies with several pharmacological targets reviewed from the data available on PubMed, Science Direct, Clinicaltrails.gov, and from many reputed foundations.

RESULTS

To highlight the clinical efficacy, safety, recent development, and stable formulation of escitalopram with an increased bioavailability profile. Evidence-based on the available clinical and pharmacoeconomic data, escitalopram represents an effective first-line treatment option for MDD patients.

CONCLUSION

The present review highlights the placebo-controlled clinical studies and the recent development that can be helpful for further research perspectives.

Identification of Photodegradation Products of Escitalopram in Surface Water by HPLC-MS/MS and Preliminary Characterization of Their Potential Impact on the Environment

The study concerns the photodegradation of the antidepressant escitalopram (ESC), the S-enantiomer of the citalopram raceme, both in ultrapure and surface water, considering the contribution of indirect photolysis through the presence of nitrate and bicarbonate. The effect of nitrate and bicarbonate concentrations was investigated by full factorial design, and only the nitrate concentration resulted in having a significant effect on the degradation. The kinetics of ESC photodegradation is the pseudo-first-order (half-life = 62.4 h in ultrapure water and 48.4 h in lake water). The generation of transformation products (TPs) was monitored through a developed and validated HPLC-MS/MS method. Fourteen TPs were identified in ultrapure water (one of them, at m/z 261, for the first time) and other two TPs at m/z 327 (found for the first time in this study) were identified only in presence of a nitrate. Several TPs were the same as those formed during the photodegradation of citalopram. The photodegradation pathway of ESC and its mechanism of degradation in water is proposed. The method was applied successfully to the analyses of surface water samples, in which a few dozen of ng L−1 of ESC was determined together with the presence of TP2, TP5 and TP12. Finally, a preliminary in silico evaluation of the toxicological profile and environmental behavior of TPs by computational models was carried out; two TPs (TP4 and TP10) were identified as of potential concern, as they were predicted mutagenic by Ames test model.

Tools for optimising pharmacotherapy in psychiatry (therapeutic drug monitoring, molecular brain imaging and pharmacogenetic tests): focus on antidepressants

Objectives: More than 40 drugs are available to treat affective disorders. Individual selection of the optimal drug and dose is required to attain the highest possible efficacy and acceptable tolerability for every patient.Methods: This review, which includes more than 500 articles selected by 30 experts, combines relevant knowledge on studies investigating the pharmacokinetics, pharmacodynamics and pharmacogenetics of 33 antidepressant drugs and of 4 drugs approved for augmentation in cases of insufficient response to antidepressant monotherapy. Such studies typically measure drug concentrations in blood (i.e. therapeutic drug monitoring) and genotype relevant genetic polymorphisms of enzymes, transporters or receptors involved in drug metabolism or mechanism of action. Imaging studies, primarily positron emission tomography that relates drug concentrations in blood and radioligand binding, are considered to quantify target structure occupancy by the antidepressant drugs in vivo. Results: Evidence is given that in vivo imaging, therapeutic drug monitoring and genotyping and/or phenotyping of drug metabolising enzymes should be an integral part in the development of any new antidepressant drug.Conclusions: To guide antidepressant drug therapy in everyday practice, there are multiple indications such as uncertain adherence, polypharmacy, nonresponse and/or adverse reactions under therapeutically recommended doses, where therapeutic drug monitoring and cytochrome P450 genotyping and/or phenotyping should be applied as valid tools of precision medicine.

Comparing the Therapeutic Effects of Crocin, Escitalopram and Co-Administration of Escitalopram and Crocin on Learning and Memory in Rats with Stress-Induced Depression

Background

Depression affects various brain functions. According to previous studies, escitalopram influences brain functions in depression and crocin reduces memory impairments. Therefore, this study aimed to compare the therapeutic effects of using crocin and escitalopram (separately and in combination) on learning and memory in rats with stress-induced depression.

Methods

Fifty-six rats were allocated into seven groups of control, sham, continuous depression, recovery period, daily injections of escitalopram, crocin and escitalopram-crocin during 14 days after inducing depression by stress. Passive avoidance (PA) test was used to assess brain functions.

Results

Latency has significant differences in depression group. Also, it significantly increased in depression-crocin, depression-escitalopram and depression-escitalopram-crocin groups compared to the depression group. The dark stay (DS) time was significantly higher in the depression and depression-recovery groups. However, the DS time significantly decreased in the depression-crocin, depression-escitalopram and depression-escitalopram-crocin groups. Furthermore, the number of entrances to the dark room was significantly lower in depression-crocin and depression-escitalopram-crocin groups compared to the depression one.

Conclusion

Different depression treatments (i.e. crocin, escitalopram and crocin-escitalopram) reduced depression-induced memory deficits. Crocin and escitalopram-crocin, respectively, improved brain functions and locomotor activity more than escitalopram. Comparatively, in subjects with depression, crocin, which is an effective saffron constituent, partially affected the memory deficits better than escitalopram (as a chemical component).

Palladium Nanoparticles Supported on Smopex-234® as Valuable Catalysts for the Synthesis of Heterocycles

Supported catalysts are important tools for developing green-economy-based processes. Palladium nanoparticles (NPs) that are immobilized on two fibers developed as metal scavengers (i.e., Smopex®-234 and Smopex®-111, 1% w/w) have been prepared and tested in copper-free cyclocarbonylative Sonogashira reactions. Their catalytic activity has been compared with that of a homogeneous catalyst (i.e., PdCl2(PPh3)2). Pd/Smopex®-234 showed high activity and selectivity in the synthesis of functionalized heterocycles, such as phthalans and isochromans, even when working with a very low amount of palladium (0.2–0.5 mol%). The extension of Pd/Smopex®-234 promoted cyclocarbonylative reactions to propargyl and homopropargyl amides afforded the corresponding isoindoline and dihydrobenzazepine derivatives. A preliminary test on Pd NPs leaching into the solution (1.7 × 10−3 mg) seems to indicate that, at the end of the reaction, almost all of the active metal is present on the fiber surface.

Squaramide-Catalyzed Asymmetric Intramolecular Oxa-Michael Reaction of α,β-Unsaturated Carbonyls Containing Benzyl Alcohol: Construction of Chiral 1-Substituted Phthalans

Organocatalytic enantioselective intramolecular oxa-Michael reactions of benzyl alcohol bearing α,β-unsaturated carbonyls as Michael acceptors are presented herein. Using cinchona squaramide-based organocatalyst, enones as well as α,β-unsaturated esters containing benzyl alcohol provided their corresponding 1,3-dihydroisobenzofuranyl-1-methylene ketones and 1,3-dihydroisobenzofuranyl-1-methylene esters in excellent yields with high enantioselectivities. In addition, enantioenriched 1,3-dihydroisobenzofuranyl-1-methylene ketone could be obtained from the Wittig/oxa-Michael reaction cascade of 1,3-dihydro-2-benzofuran-1-ol.

Predicting Antidepressant Citalopram Treatment Response via Changes in Brain Functional Connectivity After Acute Intravenous Challenge

Introduction: The early and therapy-specific prediction of treatment success in major depressive disorder is of paramount importance due to high lifetime prevalence, and heterogeneity of response to standard medication and symptom expression. Hence, this study assessed the predictability of long-term antidepressant effects of escitalopram based on the short-term influence of citalopram on functional connectivity. Methods: Twenty nine subjects suffering from major depression were scanned twice with resting-state functional magnetic resonance imaging under the influence of intravenous citalopram and placebo in a randomized, double-blinded cross-over fashion. Symptom factors were identified for the Hamilton depression rating scale (HAM-D) and Beck's depression inventory (BDI) taken before and after a median of seven weeks of escitalopram therapy. Predictors were calculated from whole-brain functional connectivity, fed into robust regression models, and cross-validated. Results: Significant predictive power could be demonstrated for one HAM-D factor describing insomnia and the total score (r = 0.45-0.55). Remission and response could furthermore be predicted with an area under the receiver operating characteristic curve of 0.73 and 0.68, respectively. Functional regions with high influence on the predictor were located especially in the ventral attention, fronto-parietal, and default mode networks. Conclusion: It was shown that medication-specific antidepressant symptom improvements can be predicted using functional connectivity measured during acute pharmacological challenge as an easily assessable imaging marker. The regions with high influence have previously been related to major depression as well as the response to selective serotonin reuptake inhibitors, corroborating the advantages of the current approach of focusing on treatment-specific symptom improvements.

The effects of acute serotonin challenge on executive planning in patients with obsessive-compulsive disorder (OCD), their first-degree relatives, and healthy controls

RATIONALE

Obsessive-compulsive disorder (OCD) is characterized by executive function impairment and by clinical responsivity to selective serotonin reuptake inhibitors (SSRIs). Executive planning deficits constitute a candidate endophenotype for OCD. It is not known whether this endophenotype is responsive to acute serotonin manipulation.

OBJECTIVE

The study aimed to investigate the effects of acute SSRI administration on executive function in patients with OCD, first-degree relatives of patients with OCD, and healthy controls.

METHODS

A randomized double-blind cross-over study assessed the effects of single-dose escitalopram (20 mg) and placebo on executive planning in 24 patients with OCD, 13 clinically unaffected first-degree relatives of patients with OCD, and 28 healthy controls. Performance on a Tower of London task measuring executive planning was assessed 4 h after oral administration of the pharmacological challenge/placebo and compared across and within groups using a mixed model analysis of variance.

RESULTS

On the outcome measure of interest, i.e., the mean number of choices to obtain the correct solution, there was a marginally significant effect of group (F(2, 59) = 3.1; p = 0.052), with patients (least square (LS) mean 1.43; standard error [SE] 0.06; 95% confidence interval (CI), 1.31-1.55) and their relatives (LS mean 1.46; SE 0.08; 95% CI, 1.30-1.62) performing worse than matched healthy controls (LS mean 1.26; SE 0.05; 95% CI, 1.15-1.37) on placebo. There was a trend towards a significant group × treatment interaction (F(2, 58) = 2.8, p = 0.069), with post hoc tests showing (i) patients (p = 0.009; LS mean difference 0.23; SE 0.08) and relatives (p = 0.03; LS mean difference 0.22; SE 0.10) were more impaired compared to controls and (ii) escitalopram was associated with improved executive planning in patients with OCD (p = 0.013; LS mean difference 0.1; SE 0.04), but not other groups (both p > 0.1; controls: LS mean difference - 0.03; SE 0.04; relatives: LS mean difference 0.02; SE 0.05).

CONCLUSION

Our findings are consistent with a view that there is impaired executive planning in OCD and that this constitutes a behavioural endophenotype. In patients with OCD, but not in relatives, acute SSRI administration ameliorated this deficit. Further investigation is needed to understand common and differential involvement of neurochemical systems in patients with OCD and their relatives.

Selective serotonin reuptake inhibitor escitalopram inhibits 5-HT3 receptor currents in NCB-20 cells

Escitalopram is one of selective serotonin reuptake inhibitor antidepressants. As an S-enantiomer of citalopram, it shows better therapeutic outcome in depression and anxiety disorder treatment because it has higher selectivity for serotonin reuptake transporter than citalopram. The objective of this study was to determine the direct inhibitory effect of escitalopram on 5-hydroxytryptamine type 3 (5-HT₃) receptor currents and study its blocking mechanism to explore additional pharmacological effects of escitalopram through 5-HT₃ receptors. Using a whole-cell voltage clamp method, we recorded currents of 5-HT₃ receptors when 5-HT was applied alone or co-applied with escitalopram in cultured NCB-20 neuroblastoma cells known to express 5-HT₃ receptors. 5-HT induced currents were inhibited by escitalopram in a concentration-dependent manner. EC₅₀ of 5-HT on 5-HT₃ receptor currents was increased by escitalopram while the maximal peak amplitude was reduced by escitalopram. The inhibitory effect of escitalopram was voltage independent. Escitalopram worked more effectively when it was co-applied with 5-HT than pre-application of escitalopram. Moreover, escitalopram showed fast association and dissociation to the open state of 5-HT₃ receptor channel with accelerating receptor desensitization. Although escitalopram accelerated 5-HT₃ receptor desensitization, it did not change the time course of desensitization recovery. These results suggest that escitalopram can inhibit 5-HT₃ receptor currents in a non-competitive manner with the mechanism of open channel blocking.

Application of LC–ESI-MS/MS Method for Analysis of Escitalopram Oxalate in Human Urine and Pharmaceutical Dosage Forms

An effective and sensitive liquid chromatographic–electrospray ionization tandem mass-spectrometric (LC–ESI-MS/MS) method was developed and validated for quantification of escitalopram oxalate (ESC-OX), antidepressant drug in spiked human urine and pharmaceutical formulations. In this work, simple liquid–liquid extraction was optimized and used for extraction of cited drug from urine samples. The chromatographic separation was attained within 6 min including re-equilibration time by using gradient elution with 0.1% formic acid in acetonitrile and 0.1% formic acid in water as mobile phase, Zorbax Eclipse RP C18 (50 × 2.1 mm) column was used with a particle size of 1.8 μm; the flow-rate was 0.35 mL min−1. Ion signal m/z 262.0 and 109.0 for ESC-OX product ions were monitored at positive ESI mode. Validation of the method was carried out according to the ICH Q2 (R1) guidelines and EMEA criteria. The method was linear over 79−196,450 pg mL−1 with a regression of 0.9999 and 0.9993 for both standard and urine samples. The LOD was 3.88 and 10.66 pg mL−1 for standard and urine samples, respectively, while lower limit of quantification was 79 pg mL−1.

The effectiveness of high-dose escitalopram in the treatment of patients suffering from schizophrenia with comorbid obsessive-compulsive disorder: an open-label study

Obsessive-compulsive disorder frequently co-occur with schizophrenia causing a significant impairment. There is a paucity of published data on the treatment of such complicated patients. It has been suggested that the combination of antipsychotics and antiobsessive agents is the best treatment for schizophrenia with obsessive-compulsive disorder; however, there is no published data regarding the use of high dose (up to 40 mg/day) escitalopram. This open-label, prospective study was designed to investigate the efficacy, short-term safety and tolerability of escitalopram in doses up to 40 mg in patients with schizophrenia and obsessive-compulsive disorder. Patients were treated with increasing doses of escitalopram for 13 weeks. Thirteen patients (86.67%) completed the study. A significant improvement was observed in the total Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) scores and in the scores of Y-BOCS-Obsession and Y-BOCS-Compulsion subscales. Furthermore, a significant improvement was observed in the total scores of the Positive and Negative Syndrome Scale and Clinical Global Impression-severity scale. Escitalopram, up to 40 mg/day was well tolerated and may be beneficial in the management of patients with schizophrenia and obsessive-compulsive disorder. Further studies are needed to confirm this finding and to assess long-term safety.

Recent Advances in Phthalan and Coumaran Chemistry

Oxygen-containing heterocycles are common in biologically active compounds. In particular, phthalan and coumaran cores are found in pharmaceuticals, organic electronics, and other useful medical and technological applications. Recent research has expanded the methods available for their synthesis. This Minireview presents recent advances in the chemistry of phthalans and coumarans, with the goal of overcoming synthetic challenges and facilitating the applications of phthalans and coumarans.

Efficacy of escitalopram oxalate for patients with post-stroke depression

This retrospective study investigated the efficacy and safety of escitalopram oxalate (ESO) for the treatment of post-stroke depression (PSD).A total of 115 patients with PSD were included in this study. A total of 65 patients underwent ESO (Intervention group). A total of 50 patients received acupressure (Control group). The outcome measurements included Montgomery-Åsberg Depression Rating Scale (MADRS), Hamilton Anxiety Rating Scale (HAM-A), and Sheehan Disability Scale (SDS). In addition, we also recorded the adverse events in this study.At the end of 8-week treatment, ESO showed greater efficacy in depression, measured by MADRS (P < .01); anxiety, measured by HAM-A scale (P < .01); and disability, measured by SDS (P < .01), compared to acupressure. Additionally, there were not significant differences regarding adverse events between two groups (P > .05).The present results indicate that ESO can decrease symptoms of patients with PSD.

Escitalopram, a selective serotonin reuptake inhibitor, inhibits voltage-dependent K+ channels in coronary arterial smooth muscle cells

We investigated the inhibitory effect of escitalopram, a selective serotonin reuptake inhibitor (SSRI), on voltage-dependent K⁺ (Kv) channels in freshly separated from rabbit coronary arterial smooth muscle cells. The application of escitalopram rapidly inhibited vascular Kv channels. Kv currents were progressively inhibited by an increase in the concentrations of escitalopram, suggesting that escitalopram inhibited vascular Kv currents in a concentration-dependent manner. The IC₅₀ value and Hill coefficient for escitalopram-induced inhibition of Kv channels were 9.54±1.33 µM and 0.75±0.10, respectively. Addition of escitalopram did not alter the steady-state activation and inactivation curves, suggesting that the voltage sensors of the channels were not affected. Pretreatment with inhibitors of Kv1.5 and/or Kv2.1 did not affect the inhibitory action of escitalopram on vascular Kv channels. From these results, we concluded that escitalopram decreased the vascular Kv current in a concentration-dependent manner, independent of serotonin reuptake inhibition.

Efficacy and tolerability of escitalopram in treatment of major depressive disorder with anxiety symptoms: a 24-week, open-label, prospective study in Chinese population

BACKGROUND

Significant anxiety symptoms are associated with poor clinical course and outcome in major depressive disorder (MDD). This single-arm, open-label study aimed to evaluate the efficacy and tolerability of escitalopram treatment in patients with MDD and anxiety symptoms.

METHODS

Adult patients with MDD and anxiety symptoms (Montgomery-Asberg Depression Rating Scale [MADRS] ≥22 and Hamilton Anxiety Rating Scale [HAM-A] ≥14) were enrolled and received escitalopram (10-20 mg/day) treatment for 24 weeks. Symptom status was assessed by MADRS, 17-item-Hamilton Depression Rating Scale, HAM-A, and Clinical Global Impression Scale at baseline and the following visits. Quality of life was assessed by Short Form-12, and safety was evaluated by adverse events, laboratory investigations, vital signs, and physical findings.

RESULTS

Overall, 200 of 318 (66.2%) enrolled patients completed the 24-week treatment. The remission (MADRS ≤10 and HAM-A ≤7) rate in the full analysis set (N=285) was 73.3% (95% confidence interval: 67.80, 78.38) at week 24. Mean (± standard deviation) MADRS total score was 33.4 (±7.13) and HAM-A score was 27.6 (±7.26) at baseline, which reduced to 6.6 (±10.18) and 6.0 (±8.39), respectively, at week 24. Patients with higher baseline depression and anxiety level took longer to achieve similar remission rates. Overall, 80 of the 302 (26.5%) patients included in the safety set reported at least 1 treatment-emergent adverse event (TEAE). Most frequently reported TEAEs (>2%) were headache (4.0%), nasopharyngitis (3.6%), nausea (3.0%), and dizziness (2.6%). Serious TEAEs were reported by 1.3% patients; no deaths were reported.

CONCLUSION

Escitalopram 10-20 mg/day was effective and well-tolerated in the long-term treatment of MDD with anxiety symptoms in adult Chinese population.

Cost-Effectiveness Analysis of Escitalopram Compared with Paroxetine in Treatment of Generalized Anxiety Disorder in the United Kingdom

Background:

Generalized anxiety disorder (GAD) is associated with substantial economic burden.

Objective:

To assess, from a societal perspective, the cost-effectiveness of escitalopram and paroxetine in the treatment of GAD in the UK.

Method:

A decision analytic model with a 9 month time horizon was adapted to the UK setting. Model inputs included drug- and nondrug-specific probabilities from head-to-head trial data, published literature, and expert opinion. Main outcome measures were success (response after 12 wk of treatment and no relapse during the following 24 wk) and costs. Resource use was based on National Institute for Health and Clinical Excellence guidance for GAD patient management, and estimated unit costs came from standard national sources. Human capital approach was used to estimate costs of absence from work. The analysis was performed from the societal perspective.

Results:

Escitalopram-treated patients were associated with 14.4% higher first-line treatment success and significantly lower discontinuation rates due to adverse events than were those treated with paroxetine. Treatment with escitalopram yielded lower expected costs with greater effectiveness compared with paroxetine. These clinical advantages led to less sick leave and resource use as a result of lower switch rates and use of secondary care. Total expected 9 month costs were £1408 ($2560 US) lower for escitalopram-treated patients than for paroxetine-treated patients. Sensitivity analyses on key parameters demonstrated robustness of the model.

Conclusions:

Escitalopram appears to be cost-effective compared with paroxetine in the treatment of GAD in the UK.

A Qualitative Review of Recent Economic Evaluations of Escitalopram

Objective:

To review published pharmacoeconomic evaluations of escitalopram.

Data Sources:

MEDLINE, EMBASE, Health Star, and Ovid Journals databases were searched using escitalopram, cost, cost-effectiveness, and economics as search terms. All articles and abstracts published from January 2003 to April 2006 were reviewed and cross-referenced for possible exclusions or duplications. Searches were not limited to English-language publications.

Study Selection and Data Extraction:

One prospective economic study and 10 studies using decision analytical models assessing the cost-effectiveness of escitalopram compared with citalopram and/or venlafaxine were identified and reviewed.

Data Synthesis:

Pharmacoeconomic studies using country-specific currency economic analysis from Europe and Canada have been conducted assessing the cost-effectiveness of escitalopram in major depression. Several studies have shown escitalopram to be more cost-effective compared with citalopram, with cost savings identified in societal and healthcare system perspectives. However, the cost-effectiveness of escitalopram was less significant when compared with venlafaxine.

Conclusions:

Economic studies suggest that escitalopram is cost-effective compared with citalopram in treatment of major depression, but has marginal advantage compared with venlafaxine.

In vivo investigation of escitalopram's allosteric site on the serotonin transporter

Escitalopram is a commonly prescribed antidepressant of the selective serotonin reuptake inhibitor class. Clinical evidence and mapping of the serotonin transporter (SERT) identified that escitalopram, in addition to its binding to a primary uptake-blocking site, is capable of binding to the SERT via an allosteric site that is hypothesized to alter escitalopram's kinetics at the SERT. The studies reported here examined the in vivo role of the SERT allosteric site in escitalopram action. A knockin mouse model that possesses an allosteric-null SERT was developed. Autoradiographic studies indicated that the knockin protein was expressed at a lower density than endogenous mouse SERT (approximately 10-30% of endogenous mouse SERT), but the knockin mice are a viable tool to study the allosteric site. Microdialysis studies in the ventral hippocampus found no measurable decrease in extracellular serotonin response after local escitalopram challenge in mice without the allosteric site compared to mice with the site (p=0.297). In marble burying assays there was a modest effect of the absence of the allosteric site, with a larger systemic dose of escitalopram (10-fold) necessary for the same effect as in mice with intact SERT (p=0.023). However, there was no effect of the allosteric site in the tail suspension test. Together these data suggest that there may be a regional specificity in the role of the allosteric site. The lack of a robust effect overall suggests that the role of the allosteric site for escitalopram on the SERT may not produce meaningful in vivo effects.

Escitalopram: better treatment for depression is through the looking glass

Depression remains a common and often devastating illness. With the introduction of the selective serotonin reuptake inhibitors in the 1980s, patients were afforded treatment for depression that was both safer and better tolerated than any prior treatment modality offered. Although selective serotonin reuptake inhibitors quickly became the most widely used medications for the treatment of depression, no single agent has been recognized as an obvious first-line choice. Chirality potentially offers one method to improve upon the selective serotonin reuptake inhibitor class. For racemic compounds that differ in stereospecificity, separation into single enantiomers can result in significant changes in potency, tolerability and efficacy. One of the most widely prescribed selective serotonin reuptake inhibitors is citalopram, which exists as a racemic mixture of R- and S-enantiomers. The S-enantiomer escitalopram (Cipralex, Lundbeck) is the therapeutically active portion of the parent compound and has a proven antidepressant efficacy. The R-enantiomer lacks activity as an antidepressant and has been shown to inhibit the effect of the S-enantiomer when the two are combined. Escitalopram is the most selective member of its class and with minimal effects on the cytochrome P450 system, has a negligible potential for drug-drug interactions. In placebo-controlled trials, escitalopram has consistently demonstrated symptomatic improvement as early as the first to second week of treatment. In addition to antidepressant efficacy, escitalopram also appears to exhibit significant anxiolytic properties. It has also shown efficacy in treating panic disorder and generalized and social anxiety disorders. This is advantageous as many patients who suffer from depression also experience comorbid anxiety disorders.

The estimation of utility weights in cost-utility analysis for mental disorders: a systematic review

OBJECTIVE

To systematically review approaches and instruments used to derive utility weights in cost-utility analyses (CUAs) within the field of mental disorders and to identify factors that may have influenced the choice of the approach.

METHODS

We searched the databases DARE (Database of Abstracts of Reviews of Effects), NHS EED (National Health Service Economic Evaluation Database), HTA (Health Technology Assessment), and PubMed for CUAs. Studies were included if they were full economic evaluations and reported quality-adjusted life-years as the health outcome. Study characteristics and instruments used to estimate utility weights were described and a logistic regression analysis was conducted to identify factors associated with the choice of either the direct (e.g. standard gamble) or the preference-based measure (PBM) approach (e.g. EQ-5D).

RESULTS

We identified 227 CUAs with a maximum in 2009, 2010, and 2012. Most CUAs were conducted in depression, dementia, or psychosis, and came from the US or the UK, with the EQ-5D being the most frequently used instrument. The application of the direct approach was significantly associated with depression, psychosis, and model-based studies. The PBM approach was more likely to be used in recent studies, dementia, Europe, and empirical studies. Utility weights used in model-based studies were derived from only a small number of studies.

LIMITATIONS

We only searched four databases and did not evaluate the quality of the included studies.

CONCLUSIONS

Direct instruments and PBMs are used to elicit utility weights in CUAs with different frequencies regarding study type, mental disorder, and country.

Efficacy and safety of generic escitalopram versus Lexapro in the treatment of major depression: a multicenter double-blinded randomized controlled trial

Background

Depression is an increasingly important public health problem in China, but only a small minority of patients with this condition receive treatment. One of the reasons for low treatment rates is the relatively high cost of imported antidepressant medications.

Aim

Compare the efficacy and safety of the generic form of the selective serotonin re-uptake inhibitory (SSRI) antidepressant escitalopram to the proprietary form of escitalopram (Lexapro) in the treatment of major depression.

Methods

A multicenter double-blinded randomized controlled trial enrolled 260 patients with depression and randomly assigned them to receive eight weeks of treatment with either generic escitalopram (n=130) or Lexapro (n=130). Efficacy was assessed by the Hamilton rating scale for depression (HAMD-17). Safety was assessed by evaluating adverse events reported by patients, regularly recording vital signs, and conducting laboratory tests and electrocardiograms.

Results

There were 35 (27%) dropouts during the 8 weeks of treatment in the generic escitalopram group and 32 (25%) in the Lexapro group. In the intention-to-treat analysis (i.e., including all patients) the mean (s.d.) drop in the HAMD total score at the end of the 8th week of treatment was 13.9 (8.2) in the generic escitalopram group and 14.3 (8.1) in the Lexapro group (t=0.44, p=0.664). The proportions of patients responsive to treatment (i.e., >50% drop in total HAMD score) were 69% and 67% in the generic escitalopram group and Lexapro group, respectively (χ²=0.16, df=1, p=0.690; and the proportions that achieved remission (i.e., final HAMD <7) were 51% and 49% (χ²=0.06, df=1, p=0.804). The most frequently reported adverse events were dry mouth (12.3%), nausea (9.2 %) and dizziness (6.2%) in the generic escitalopram group and nausea (10.8%), fainting (7.7%) and drowsiness (6.9%) in the Lexapro group. During the first 35 days of treatment, one suicide and two suicide attempts occurred in the generic escitalopram group and one suicide occurred in the Lexapro group (Fisher exact test, p=0.314).

Conclusion

Generic escitalopram is as effective and safe as Lexapro in the initial treatment of patients with moderate to severe episodes of major depression who seek treatment in the outpatient departments of psychiatric hospitals in China. Careful monitoring of the risk of suicidal events is an essential component of the treatment of depressed patients.

Trial registration

NCT00866593 (clinical.trails.gov)

Escitalopram for the management of major depressive disorder: a review of its efficacy, safety, and patient acceptability

Escitalopram (escitalopram oxalate; Cipralex(®), Lexapro(®)) is a selective serotonin reuptake inhibitor (SSRI) used for the treatment of major depressive disorder (MDD) and anxiety disorder. This drug exerts a highly selective, potent, and dose-dependent inhibitory effect on the human serotonin transport. By inhibiting the reuptake of serotonin into presynaptic nerve endings, this drug enhances the activity of serotonin in the central nervous system. Escitalopram also has allosteric activity. Moreover, the possibility of interacting with other drugs is considered low. This review covers randomized, controlled studies that enrolled adult patients with MDD to evaluate the efficacy of escitalopram based on the Montgomery-Asberg Depression Rating Scale and the Hamilton Depression Rating Scale. The results showed that escitalopram was superior to placebo, and nearly equal or superior to other SSRIs (eg, citalopram, paroxetine, fluoxetine, sertraline) and serotonin-noradrenaline reuptake inhibitors (eg, duloxetine, sustained-release venlafaxine). In addition, with long-term administration, escitalopram has shown a preventive effect on MDD relapse and recurrence. Escitalopram also showed favorable tolerability, and associated adverse events were generally mild and temporary. Discontinuation symptoms were milder with escitalopram than with paroxetine. In view of the patient acceptability of escitalopram, based on both a meta-analysis and a pooled analysis, this drug was more favorable than other new antidepressants. The findings indicate that escitalopram achieved high continuity in antidepressant drug therapy.

Comparative efficacy of escitalopram in the treatment of major depressive disorder

BACKGROUND

Escitalopram is an allosteric selective serotonin reuptake inhibitor (SSRI) with some indication of superior efficacy in the treatment of major depressive disorder. In this systematic review, we critically evaluate the evidence for comparative efficacy and tolerability of escitalopram, focusing on pooled and meta-analysis studies.

METHODS

A literature search was conducted for escitalopram studies that quantitatively synthesized data from comparative randomized controlled trials in MDD. Studies were excluded if they did not focus on efficacy, involved primarily subgroups of patients, or synthesized data included in subsequent studies. Outcomes extracted from the included studies were weighted mean difference or standard mean difference, response and remission rates, and withdrawal rate owing to adverse events.

RESULTS

The search initially identified 24 eligible studies, of which 12 (six pooled analysis and six meta-analysis studies) met the criteria for review. The pooled and meta-analysis studies with citalopram showed significant but modest differences in favor of escitalopram, with weighted mean differences ranging from 1.13 to 1.73 points on the Montgomery Asberg Depression Rating Scale, response rate differences of 7.0%-8.3%, and remission rate differences of 5.1%-17.6%. Pooled analysis studies showed efficacy differences compared with duloxetine and with serotonin noradrenaline reuptake inhibitors combined, but meta-analysis studies did not. The effect sizes of the efficacy differences increased in the severely depressed patient subgroups.

CONCLUSION

Based on pooled and meta-analysis studies, escitalopram demonstrates superior efficacy compared with citalopram and with SSRIs combined. Escitalopram shows similar efficacy to serotonin noradrenaline reuptake inhibitors but the number of trials in these comparisons is limited. Efficacy differences are modest but clinically relevant, especially in more severely depressed patients.

Structure-activity relationships for a novel series of citalopram (1-(3-(dimethylamino)propyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile) analogues at monoamine transporters

(+/-)-Citalopram (1, 1-(3-(dimethylamino)propyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile), and its eutomer, escitalopram (S-(+)-1) are selective serotonin reuptake inhibitors (SSRIs) that are used clinically to treat anxiety and depression. To further explore structure-activity relationships at the serotonin transporter (SERT), a series of (+/-)-4- and 5-substituted citalopram analogues were designed, synthesized, and evaluated for binding at the SERT, dopamine transporter (DAT) and norepinephrine transporter (NET) in native rodent tissue. Many of these analogues showed high SERT binding affinities (Ki=1-40 nM) and selectivities over both NET and DAT. Selected enantiomeric pairs of analogues were synthesized and both retained enantioselectivity as with S- and R-1, wherein S>R at the SERT. In addition, the enantiomeric pairs of 1 and 5 were tested for binding at the homologous bacterial leucine transporter (LeuT), wherein low affinities and the absence of enantioselectivity suggested distinctive binding sites for these compounds at SERT as compared to LeuT. These novel ligands will provide molecular tools to elucidate drug-protein interactions at the SERT and to relate those to behavioral actions in vivo.

Escitalopram: a review of its use in the management of major depressive disorder in adults

Escitalopram (escitalopram oxalate; Cipralex, Lexapro), a selective serotonin reuptake inhibitor (SSRI) indicated for the treatment of major depressive disorder (MDD), demonstrates a highly selective and potent, dose-dependent inhibition of the human serotonin transporter, inhibiting serotonin reuptake into presynaptic nerve terminals and thus increasing serotonergic activity in the CNS. With regard to primary endpoints (such as improved scores on the Montgomery-Asberg Depression Rating Scale [MADRS] and the Hamilton Depression Rating Scale [HAM-D]), escitalopram was generally more effective than placebo, at least as effective as citalopram, and generally at least as effective as other comparator drugs, including the SSRIs fluoxetine, paroxetine and sertraline, the serotonin-noradrenaline (norepinephrine) reuptake inhibitors (SNRIs) venlafaxine extended release and duloxetine, and the aminoketone bupropion in adult patients with MDD in short-term, well designed trials. Moreover, it demonstrated a rapid onset of antidepressant action. Escitalopram was also found to be cost effective in several studies, dominating other SSRIs and venlafaxine extended release. Maintenance therapy is commonly required to prevent recurrence of depression. Long-term trials corroborated short-term results, with escitalopram demonstrating greater efficacy than placebo in relapse prevention. Additionally, escitalopram was at least as effective as citalopram, paroxetine and duloxetine in long-term comparative trials. Escitalopram has a predictable tolerability profile with generally mild to moderate and transient adverse events, and a low propensity for drug interactions. Sexual dysfunction with escitalopram treatment appeared to occur to a similar or lower extent to that with paroxetine (another SSRI), to a similar or greater extent to that with the SNRI duloxetine, and to a greater extent than that with the aminoketone bupropion. Thus, escitalopram is an effective and generally well tolerated treatment for moderate to severe MDD. Escitalopram, like other SSRIs, is an effective first-line option in the management of patients with MDD.

Serotonergic modulation of response inhibition and re-engagement? Results of a study in healthy human volunteers

OBJECTIVE

Cognitive functions dependent on the prefrontal cortex, such as the ability to suppress behavior (response inhibition) and initiate a new one (response re-engagement) is important in the activities of daily life. Central serotonin (5-HT) function is thought to be a critical component of these cognitive functions. In recent studies, 5-HT failed to affect stop-signal reaction time (SSRT), a fundamental process in behavioral inhibition. We were interested if response inhibition and re-engagement are influenced through central 5-HT activity as mediated via the 5-HT transporter.

METHODS

Here, using a stop-change task, we investigated the effects of acute and repeated treatment with 10 mg escitalopram, a selective 5-HT reuptake inhibitor, in 36 healthy human volunteers on response inhibition and re-engagement in a randomized, double-blind, placebo-controlled study with cross-over design.

RESULTS

Results do not show an influence of escitalopram on response inhibition or response re-engagement as we did not find differences in SSRT or change reaction time (CRT).

CONCLUSIONS

These findings support the results of previous studies suggesting that 5-HT is not critical in inhibition of already initiated responses and response re-engagement. We hypothesize that results are due to different forms of behavioral inhibition and 5-HT may critical to other forms.

Effect of escitalopram on the processing of emotional faces

Serotonin has been implicated in the neurobiology of depressive and anxiety disorders, but little is known about its role in the modulation of basic emotional processing. The aim of this study was to determine the effect of the selective serotonin reuptake inhibitor, escitalopram, on the perception of facial emotional expressions. Twelve healthy male volunteers completed two experimental sessions each, in a randomized, balanced order, double-blind design. A single oral dose of escitalopram (10 mg) or placebo was administered 3 h before the task. Participants were presented to a task composed of six basic emotions (anger, disgust, fear, happiness, sadness, and surprise) that were morphed between neutral and each standard emotion in 10% steps. Escitalopram facilitated the recognition of sadness and inhibited the recognition of happiness in male, but not female faces. No drug effect on subjective measures was detected. These results confirm that serotonin modulates the recognition of emotional faces, and suggest that the gender of the face can have a role in this modulation. Further studies including female volunteers are needed.

Differential effects of escitalopram on attention: a placebo-controlled, double-blind cross-over study

RATIONALE

The role of serotonin (5-HT) in attention is not fully understood yet.

OBJECTIVE

We aimed to investigate whether attention is modulated after treatment with escitalopram, a selective serotonin reuptake inhibitor (SSRI).

METHODS

We administered 10 mg of escitalopram to 20 healthy subjects in a placebo-controlled, double-blind cross-over design for 1 day or to another 20 participants for a period of 7 days. Attention was assessed at time of plasma peak escitalopram concentration using the computerised Attention Network Test (ANT), which is a combined flanker and cued reaction time task.

RESULTS

The results showed differential effects of serotonergic manipulation on attention depending on sequence of intake. For the acute treatment, we found significant differences between escitalopram and placebo for all warning conditions dependent of sequence of intake: participants receiving escitalopram as first treatment showed significant slower reaction times in all warning conditions as compared with placebo while participants receiving escitalopram as second treatment showed significant faster reaction times as compared with placebo. For the sub-chronic treatment, we found significant differences between escitalopram and placebo depending on sequence of intake, but only for the flanker condition: participants receiving escitalopram first had significant slower reaction times in incongruent trials with escitalopram as compared with placebo while participants starting with placebo had significant shorter reaction times in incongruent trials with escitalopram.

CONCLUSIONS

Thus, the results showed a differential effect of escitalopram in cognition, especially in attention, and are discussed with regard to an interaction between serotonin and familiarity with the attention test.

Subchronic SSRI administration reduces insula response during affective anticipation in healthy volunteers

The anterior cingulate cortex (ACC) and insula are important neural substrates for the integration of cognitive, emotional, and physiological information, as well as the coordination of responses to anticipated stimuli. Increased neural activation within these structures has been observed in individuals with anxiety and depressive disorders. Selective serotonin reuptake inhibitors (SSRIs) are among the most effective and frequently prescribed anxiolytic agents, yet it is not known whether ACC or insula underlie the effects of these drugs. We examined whether subchronic administration of a SSRI to healthy volunteers attenuates activation in ACC or insula during anticipation, an important emotional process underlying anxiety. Support for this hypothesis would help to understand where and by what process SSRIs may exert beneficial effects as anxiolytics and would provide further mechanistic evidence for functional magnetic resonance imaging (fMRI) as a biomarker for the development of anxiolytics. Fifteen volunteers participated in a double-blind, placebo-controlled, randomized cross-over study. Participants completed a pleasant and aversive picture-cued anticipation task during fMRI after taking either escitalopram (10 mg) or placebo for 21 d. We found that escitalopram significantly decreased activation in bilateral posterior and middle insula during the anticipation condition irrespective of stimulus valence and in medial prefrontal and ACC during anticipation of aversive vs. pleasant images. Reduced insular and ACC activation in healthy controls during anticipation may be integral to the therapeutic efficacy of SSRIs and may provide a mechanistic approach for the use of pharmaco-fMRI in the identification of novel pharmacotherapeutic agents in patient populations.

Portal infusion of escitalopram enhances hepatic glucose disposal in conscious dogs

To examine whether escitalopram enhances net hepatic glucose uptake during a hyperinsulinemic hyperglycemic clamp, studies were performed in conscious 42-h-fasted dogs. The experimental period was divided into P1 (0-90 min) and P2 (90-270 min). During P1 and P2 somatostatin (to inhibit insulin and glucagon secretion), 4x basal intraportal insulin, basal intraportal glucagon, and peripheral glucose (2x hepatic glucose load) were infused. Saline was infused intraportally during P1 in all groups. In one group saline infusion was continued in P2 (SAL, n = 11), while escitalopram was infused intraportally at 2 microg/kg/min (L-ESC, n = 6) or 8 microg/kg/min (H-ESC, n = 7) during P2 in two other groups. The arterial insulin concentrations rose approximately four fold (to 123 +/- 8, 146 +/- 13 and 148 +/- 15 pmol/L) while glucagon concentrations remained basal (41 +/- 3, 44 +/- 9 and 40 +/- 3 ng/L) in all groups. The hepatic glucose load averaged 216 +/- 13, 223 +/- 19 and 202 +/- 12 micromol/kg/min during the entire experimental period (P1 and P2) in the SAL, L-ESC and H-ESC groups, respectively. Net hepatic glucose uptake was 11.6 +/- 1.4, 10.1 +/- 0.9 and 10.4 +/- 2.3 micromol/kg/min in P1 and averaged 16.9 +/- 1.5, 15.7 +/- 1.3 and 22.6 +/- 3.7 (P < 0.05) in the SAL, L-ESC and H-ESC groups, respectively during the last hour of P2 (210-270 min). Net hepatic carbon retention (glycogen storage) was 15.4 +/- 1.3, 14.9 +/- 0.6 and 20.9 +/- 2.6 (P < 0.05) micromol/kg/min in SAL, L-ESC and H-ESC respectively during the last hour of P2. Escitalopram enhanced net hepatic glucose uptake and hepatic glycogen deposition, showing that it can improve hepatic glucose clearance under hyperinsulinemic hyperglycemic conditions. Its use in individuals with diabetes may, therefore, result in improved glycemic control.

The effect of reporting methods for dosing times on the estimation of pharmacokinetic parameters of escitalopram

The objective of this study was to compare population pharmacokinetic models of escitalopram developed from dosage times recorded by a medication event monitoring system (MEMS) versus the reported times from patients with diagnosed depression. Seventy-three patients were prescribed doses of 10, 15, or 20 mg escitalopram daily. Sparse blood samples were collected at weeks 4, 12, 24, and 36 with 185 blood samples obtained from the 73 patients. NONMEM was used to develop a population pharmacokinetic model based on dosing records obtained from MEMS prior to each blood sample time. A separate population pharmacokinetic analysis using NONMEM was performed for the same population using the patient-reported last dosing time and assuming a steady-state condition as the model input. Objective function values and goodness-of-fit plots were used as model selection criteria. The absolute mean difference in the last dosing time between MEMS and patient-reported times was 4.48 +/- 10.12 hours. A 1-compartment model with first-order absorption and elimination was sufficient for describing the data. Estimated oral clearance (CL/F) to escitalopram was statistically insensitive to reported dosing methods (MEMS vs patient reported: 25.5 [7.0%] vs 26.9 [6.6%] L/h). However, different dosing report methods resulted in significantly different estimates on the volume of distribution (V/F; MEMS vs patient reported: 1000 [17.3%] vs 767 [17.5%] L) and the absorption rate constant K(a) (MEMS vs patient reported: 0.74 [45.7%] vs 0.51 [35.4%] h(-1)) for escitalopram. Furthermore, the parameters estimated from the MEMS method were similar to literature reported values for V/F ( approximately 1100 L) and K(a) ( approximately 0.8-0.9 h(-1)) arising from traditional pharmacokinetic approaches.

Serum concentrations of antidepressant drugs in a naturalistic setting: compilation based on a large therapeutic drug monitoring database

A compilation of therapeutic drug monitoring data for 15 antidepressant drugs in a naturalistic routine clinical setting is presented. A substantial number of serum concentrations, at different daily doses, are outlined, and the intraindividual and overall serum concentration coefficient of variation for a respective substance is presented. Also, concentration comparisons between women and men, and patients older or younger than 65 years are made. The drugs included are amitriptyline (n = 394), citalopram (n = 5457), clomipramine (n = 400), escitalopram (n = 3066), fluoxetine (n = 793), fluvoxamine (n = 165), mianserin (n = 1063), mirtazapine (n = 1427), moclobemide (n = 200), nortriptyline (n = 206), paroxetine (n = 1677), reboxetine (n = 85), sertraline (n = 2998), trimipramine (n = 158), and venlafaxine (n = 1781). Of the 9 drugs exhibiting linear (first order) kinetics, all but reboxetine gave a significant negative dose-to-dose-normalized correlation with concentrations, that is an increased clearance with higher dose. When dose was correlated to the metabolite:parent substance ratio for drugs exhibiting linear kinetics, citalopram and mianserin gave a positive slope, contrary to a negative slope shown for sertraline and venlafaxine. The intraindividual variations of the serum concentrations were lower than the overall variations, and the intraindividual variation of the metabolite:parent substance ratio was lower than the intraindividual variation of respective parent substance (except clomipramine and mianserin). Women had significantly higher serum concentrations than men (significant for citalopram, escitalopram, mianserin, mirtazapine, and venlafaxine), and patients older than 65 years had higher serum concentrations than the younger ones for all drugs except amitriptyline, moclobemide, and trimipramine. By presenting a comprehensive compilation of therapeutic drug monitoring data for each drug, a reference tool is created, in addition to improved pharmacokinetic knowledge of antidepressant drugs.

Psychotherapeutic benefits of opioid agonist therapy

Opioids have been used for centuries to treat a variety of psychiatric conditions with much success. The so-called "opium cure" lost popularity in the early 1950s with the development of non-addictive tricyclic antidepressants and monoamine oxidase inhibitors. Nonetheless, recent literature supports the potent role of methadone, buprenorphine, tramadol, morphine, and other opioids as effective, durable, and rapid therapeutic agents for anxiety and depression. This article reviews the medical literature on the treatment of psychiatric disorders with opioids (notably, methadone and buprenorphine) in both the non-opioid-dependent population and in the opioid-dependent methadone maintenance population. The most recent neurotransmitter theories on the origin of depression and anxiety will be reviewed, including current information on the role of serotonin, N-Methyl d-Aspartate, glutamate, cortisol, catecholamine, and dopamine in psychiatric disorders. The observation that methadone maintenance patients with co-existing psychiatric morbidity (so called dual diagnosis patients) require substantially higher methadone dosages by between 20% and 50% will be explored and qualified. The role of methadone and other opioids as beneficial psychiatric medications that are independent of their drug abuse mitigating properties will be discussed. The mechanisms by which methadone and other opioids can favorably modulate the neurotransmitter systems controlling mood will also be discussed.

Daily process methodology for measuring earlier antidepressant response

OBJECTIVE

Rapid onset of therapeutic action for antidepressant medication represents a major area of unmet medical need, and any such effects have been difficult to detect using standard study designs and measurement strategies. We conducted a randomized, open-label study with blinded raters using daily process assessment vs. standard weekly assessment to answer the following study questions: 1) is it possible to detect an antidepressant response more rapidly with daily assessment than with standard assessment approaches? 2) what is the burden of daily assessment on participants relative to standard clinical assessments? and 3) does the process of completing daily assessments have any effect on clinic-based assessments such as the Hamilton Depression Rating Scale (HAM-D)?

METHOD

Seventy-eight outpatients with major depressive disorder who received open-label fluoxetine were randomized to standard weekly clinic assessment or standard weekly clinic assessment plus daily assessment, and were followed for 28 days. Data were collected between September, 2002 and August, 2003.

RESULTS

Daily assessment appeared to have no effect on 17-item HAM-D or MADRS scores obtained in the clinic. Survival analyses revealed that daily diaries detected therapeutic effects more quickly than did standard weekly clinic assessments, across most endpoints. Perceived burden of study participation was not significantly increased by daily diary completion, nor reflected in higher dropout rates.

CONCLUSION

Daily process assessment improves the ability to detect an early antidepressant response.

An examination of acute changes in serotonergic neurotransmission using the loudness dependence measure of auditory cortex evoked activity: effects of citalopram, escitalopram and sertraline

OBJECTIVE

The underlying effect of serotonergic neurotransmission has been implicated in several psychiatric disorders. The inability to routinely and non-invasively determine the integrity of the serotonergic system in vivo has limited our understanding of disorders with a putative serotonergic abnormality. The loudness dependence of the auditory evoked potential (LDAEP) has been proposed as a reliable measure of central serotonin function in humans. While animal studies suggest that the LDAEP is sensitive to changes in central serotonin neurotransmission, evidence in humans has been indirect and inconsistent. The aim of this study was to assess the sensitivity of the LDAEP to acute augmentation in central serotonergic neurotransmission in humans.

METHODS

The study used a double-blind, placebo-controlled cross-over design, in which healthy subjects were tested under four acute treatment conditions, with pharmacologically equivalent single doses of placebo, escitalopram (10 mg), citalopram (20 mg) and sertraline (50 mg) to examine the direct effect of acute enhancement of synaptic serotonin on the LDAEP. Furthermore, the outcome of the serotonergic modulatory effects on the LDAEP was also examined using two methods (dipole source analysis (DSA) vs. scalp analysis).

RESULTS

Escitalopram, citalopram and sertraline had no effects on the LDAEP and were independent of the analysis method used.

CONCLUSION

These findings question the sensitivity of the LDAEP to acute changes in serotonin neurotransmission and its validity as a reliable measure of central serotonin function in humans.

Escitalopram effects on insula and amygdala BOLD activation during emotional processing

RATIONALE

The amygdala and insular cortex are integral to the processing of emotionally salient stimuli. We have shown in healthy volunteers that an anxiolytic agent, lorazepam, dose-dependently attenuates activation of limbic structures.

OBJECTIVE

The current study investigated whether administration of a selective serotonin reuptake inhibitor (SSRI), escitalopram, alters the activation of limbic structures. We hypothesized that subchronic (21 days) SSRI treatment attenuates the activation of the amygdala and insula during processing of emotional faces.

MATERIALS AND METHODS

Thirteen healthy volunteers participated in a double-blind, placebo-controlled, crossover, randomized study. After 21 days of treatment with either escitalopram or placebo, participants underwent functional magnetic resonance imaging (fMRI) during which all subjects completed an emotion face assessment task, which has been shown to elicit amygdala and insula activation.

RESULTS

Subjects activated the bilateral insula and amygdala after treatment with both escitalopram and placebo. In subjects who were adherent to the protocol (as evidenced by sufficiently high urine concentrations of escitalopram), a reduction in amygdala activation was seen in the escitalopram condition compared to placebo.

CONCLUSION

The current investigation provides further evidence for the mechanism of action of SSRIs through the attenuation of activation in brain regions responsible for emotion processing and provides support for the use of blood oxygenation level-dependent fMRI with pharmacological probes to help identify the specific therapeutic effect of these agents in patients with anxiety and mood disorders.