Haloperidol's introduction in the United States: A tale of a failed trial and its consequences

Haloperidol, the first butyrophenone neuroleptic, was created in Europe by Janssen Pharmaceuticals in 1958 and was introduced swiftly throughout the continent with great enthusiasm. On September 15, 1959, at Janssen's headquarters in Belgium, teams from around Europe praised the effectiveness of haloperidol. In the United States, on the contrary, its introduction was a tremendous failure, plagued by accusations of inefficacy and patent disputes. A clinical trial in Manhattan has been blamed for this commercial failure. The results of the Manhattan trial were seen as radically different from the results obtained in continental Europe. This divide would have considerable impact not only with regard to haloperidol's path on both sides of the Atlantic, but also possibly on the practical experience and theoretical construction of psychiatry. This article tries to reconstruct the story of that trial based mainly on published papers and interviews. Exploring how societal changes and issues of gender and race shaped this process, this investigation attempts to understand and contextualize different possible reasons for this Atlantic rift.

Review of Dopamine Antagonists for Nausea and Vomiting in Palliative Care Patients

Symptoms of nausea and vomiting are common in palliative care and hospice patients. One of the many classes of medications used for the treatment of nausea and vomiting is dopamine receptor antagonists which are particularly helpful for treating nausea mediated by the chemoreceptor trigger zone (CTZ) and impaired gastrointestinal function. While dopamine antagonists can be very effective treatments for nausea they should be used with caution as they carry the risk of QTc prolongation, have a FDA black box warning for tardive dyskinesia (TD), and increased risk of precipitating psychosis and death in patients with dementia. This review will cover haloperidol, olanzapine, prochlorperazine, and metoclopramide for treatment of nausea and vomiting including evidence of efficacy, pharmacokinetics, and pharmacodynamics to improve safe and effective utilization in clinical practice. This includes medication receptor site affinities at histaminic, muscarinic, serotonergic, and alpha-adrenergic receptors which can help providers anticipate potential adverse effects and risk of extrapyramidal symptoms (EPS), TD, and QTc prolongation. This review also includes considerations for dose adjustments based on renal function, hepatic function, and age. Understanding the pharmacology of dopamine antagonists can help providers choose the best treatment for control of nausea and vomiting and subsequently improve patients' quality of life.

Effects of chronic haloperidol treatment on the expression of fear memory and fear memory extinction in the cued fear-conditioned rats

AIM

Impairments in emotional memory are frequently observed in several mental disorders, highlighting their significance as potential therapeutic targets. Recent research on the cued fear conditioning model has elucidated the neural circuits involved in fear memory processing. However, contradictory findings have been reported concerning the role of dopamine and the impact of dopamine D2 receptor (D2R) antagonists. There is notably limited knowledge regarding the clinical utility of chronic D2R antagonist treatments. This study aimed to uncover how such treatments affect fear memory processing.

METHODS

We utilized a cued fear conditioning rat model and conducted chronic haloperidol treatment for 14 days. Subsequently, to investigate the effect of chronic haloperidol treatment on fear-conditioned memory expression and extinction, we observed freezing behavior under exposure to a conditioned stimulus for 14 days.

RESULTS

Chronic haloperidol treatment suppressed freezing time on the fear memory expression. In contrast, a single haloperidol administration enhanced the freezing time on fear memory expression and delayed extinction.

CONCLUSION

The results of this study suggest that chronic administration of antipsychotic drugs affects fear memory processing differently from single-dose administration. This indicates that the effects of chronic D2R antagonist treatment are distinct from the nonspecific effects of the drugs. This study provides fundamental insights that may contribute to our understanding of therapeutic mechanisms for fear memory disorders related to D2R in the future.

NMDA glutamate receptor antagonist MK-801 induces proteome changes in adult human brain slices which are partially counteracted by haloperidol and clozapine

Deciphering the molecular pathways associated with N-methyl-D-aspartate receptor (NMDAr) hypofunction and its interaction with antipsychotics is necessary to advance our understanding of the basis of schizophrenia, as well as our capacity to treat this disease. In this regard, the development of human brain-derived models that are amenable to studying the neurobiology of schizophrenia may contribute to filling the gaps left by the widely employed animal models. Here, we assessed the proteomic changes induced by the NMDA glutamate receptor antagonist MK-801 on human brain slice cultures obtained from adult donors submitted to respective neurosurgery. Initially, we demonstrated that MK-801 diminishes NMDA glutamate receptor signaling in human brain slices in culture. Next, using mass-spectrometry-based proteomics and systems biology in silico analyses, we found that MK-801 led to alterations in proteins related to several pathways previously associated with schizophrenia pathophysiology, including ephrin, opioid, melatonin, sirtuin signaling, interleukin 8, endocannabinoid, and synaptic vesicle cycle. We also evaluated the impact of both typical and atypical antipsychotics on MK-801-induced proteome changes. Interestingly, the atypical antipsychotic clozapine showed a more significant capacity to counteract the protein alterations induced by NMDAr hypofunction than haloperidol. Finally, using our dataset, we identified potential modulators of the MK-801-induced proteome changes, which may be considered promising targets to treat NMDAr hypofunction in schizophrenia. This dataset is publicly available and may be helpful in further studies aimed at evaluating the effects of MK-801 and antipsychotics in the human brain.

Concomitant use of hydroxyzine and haloperidol did not worsen delirium in patients with cancer: A multicenter, retrospective, observational study

OBJECTIVES

There is concern that hydroxyzine exacerbates delirium, but a recent preliminary study suggested that the combination of haloperidol and hydroxyzine was effective against delirium. This study examined whether the concomitant use of hydroxyzine and haloperidol worsened delirium in patients with cancer.

METHODS

This retrospective, observational study was conducted at 2 general hospitals in Japan. The medical records of patients with cancer who received haloperidol for delirium from July to December 2020 were reviewed. The treatments for delirium included haloperidol alone or haloperidol combined with hydroxyzine. The primary outcome was the duration from the first day of haloperidol administration to the resolution of delirium, defined as its absence for 2 consecutive days. The time to delirium resolution was analyzed to compare the haloperidol group and hydroxyzine combination group using the log-rank test with the Kaplan-Meier method. Secondary outcomes were (1) the total dose of antipsychotic medications, including those other than haloperidol (measured in chlorpromazine-equivalent doses), and (2) the frequencies of detrimental incidents during delirium, specifically falls and self-removal of drip infusion lines. The unpaired t-test and Fisher's exact test were used to analyze secondary outcomes.

RESULTS

Of 497 patients who received haloperidol, 118 (23.7%) also received hydroxyzine. No significant difference in time to delirium resolution was found between the haloperidol group and the hydroxyzine combination group (log-rank test, P = 0.631). No significant difference between groups was found in either chlorpromazine-equivalent doses or the frequency of detrimental incidents.

SIGNIFICANCE OF RESULTS

This study showed that the concomitant use of hydroxyzine and haloperidol did not worsen delirium in patients with cancer.

Sex-Specific Effects of Long-Term Antipsychotic Drug Treatment on Adipocyte Tissue and the Crosstalk to Liver and Brain in Rats

Antipsychotic drug (APD) medication can lead to metabolic dysfunctions and weight gain, which together increase morbidity and mortality. Metabolically active visceral adipose tissue (VAT) in particular plays a crucial role in the etiopathology of these metabolic dysregulations. Here, we studied the effect of 12 weeks of drug medication by daily oral feeding of clozapine and haloperidol on the perirenal fat tissue as part of VAT of male and female Sprague Dawley rats in the context of complex former investigations on brain, liver, and blood. Adipocyte area values were determined, as well as triglycerides, non-esterified fatty acids (NEFAs), glucose, glycogen, lactate, malondialdehyde equivalents, ferric iron and protein levels of Perilipin-A, hormone-sensitive-lipase (HSL), hepcidin, glucose transporter-4 (Glut-4) and insulin receptor-ß (IR-ß). We found increased adipocyte mass in males, with slightly higher adipocyte area values in both males and females under clozapine treatment. Triglycerides, NEFAs, glucose and oxidative stress in the medicated groups were unchanged or slightly decreased. In contrast to controls and haloperidol-medicated rats, perirenal adipocyte mass and serum leptin levels were not correlated under clozapine. Protein expressions of perilipin-A, Glut-4 and HSL were decreased under clozapine treatment. IR-ß expression changed sex-specifically in the clozapine-medicated groups associated with higher hepcidin levels in the perirenal adipose tissue of clozapine-treated females. Taken together, clozapine and haloperidol had a smaller effect than expected on perirenal adipose tissue. The perirenal adipose tissue shows only weak changes in lipid and glucose metabolism. The main changes can be seen in the proteins examined, and probably in their effect on liver metabolism.

Effectiveness and Safety of Intravenous Medications for the Management of Acute Disturbance (Agitation and Other Escalating Behaviors): A Systematic Review of Prospective Interventional Studies

Acute disturbance is a broad term referring to escalating behaviors secondary to a change in mental state, such as agitation, aggression, and violence. Available management options include de-escalation techniques and rapid tranquilization, mostly via parenteral formulations of medication. While the intramuscular route has been extensively studied in a range of clinical settings, the same cannot be said for intravenous (IV); this is despite potential benefits, including rapid absorption and complete bioavailability. This systematic review analyzed existing evidence for effectiveness and safety of IV medication for management of acute disturbances. It followed a preregistered protocol (PROSPERO identification CRD42020216456) and is reported following the guidelines set by Preferred Reporting Items for Systematic Review and Meta-Analysis. APA PsycINFO, MEDLINE, and EMBASE databases were searched for eligible interventional studies up until May 30th, 2023. Data analysis was limited to narrative synthesis since primary outcome measures varied significantly. Results showed mixed but positive results for the effectiveness of IV dexmedetomidine, lorazepam, droperidol, and olanzapine. Evidence was more limited for IV haloperidol, ketamine, midazolam, chlorpromazine, and valproate. There was no eligible data on the use of IV clonazepam, clonidine, diazepam, diphenhydramine, propranolol, ziprasidone, fluphenazine, carbamazepine, or promethazine. Most studies reported favorable adverse event profiles, though they are unlikely to have been sufficiently powered to pick up rare serious events. In most cases, evidence was of low or mixed quality, accentuating the need for further standardized, large-scale, multi-arm randomized controlled trials with homogeneous outcome measures. Overall, this review suggests that IV medications may offer an effective alternative parenteral route of administration in acute disturbance, particularly in general hospital settings.

Evaluation of the Efficacy and Safety of Quetiapine in the Treatment of Delirium in Adult ICU Patients: A Retrospective Comparative Study

Background: Quetiapine is commonly prescribed off-label to manage delirium in intensive care unit (ICU) patients. However, limited studies comparing its efficacy and safety to those of other antipsychotics exist in the literature. Method: A retrospective, single-center chart review study was conducted on adults admitted to the ICU between January 2017 and August 2022, who were diagnosed with delirium and treated with a single antipsychotic and had no neurological medical conditions, active alcohol withdrawal, or prior use of antipsychotics. Data were analyzed using SPSS software version 28, with p-values of <0.05 indicating statistical significance. Results: In total, 47 patients were included, of whom 22 (46.8%), 19 (40.4%), 4 (8.5%), and 2 (4.3%) were on quetiapine, haloperidol, risperidone, and olanzapine, respectively. The median number of hours needed to resolve delirium were 12 (21.5), 23 (28), 13 (13.75), and 36 (10) (p = 0.115) for quetiapine, haloperidol, risperidone, and olanzapine, respectively, with haloperidol being used for a significantly shorter median number of days than quetiapine (3 (2.5) days vs. 7.5 (11.5) days; p = 0.007). Of the medication groups, only quetiapine-treated patients received a significantly higher median maintenance compared to the initiation dose (50 (50) mg vs. 50 (43.75) mg; p = 0.039). For the length of stay in the ICU and hospital, delirium-free days, % of ICU time spent in delirium, ventilator-free days, the difference between the highest and baseline QTc intervals, and ICU and hospital mortalities, no significant difference was observed between the groups. Conclusions: Overall, the use of quetiapine in our retrospective study seems to not be advantageous over the other drugs in terms of efficacy and safety outcomes.

Perphenazine in Treatment-Resistant Schizophrenia

Antipsychotics are considered a gold standard treatment for schizophrenia. However, there is considerable variation in antipsychotic medication choice. Factors considered involved include symptomatology, prior response, and adverse reactions. This case report presents a 38-year-old male patient with schizophrenia in acute psychosis refractory to several antipsychotics. Hypotheses for the mechanism of action of antipsychotics and psychopharmacology are discussed, and treatment resistance is defined. The patient's psychiatric, medical, and social history and past antipsychotic medications are reviewed. Afterward, the rationale for initiating perphenazine is discussed, and the patient's improvement with this medication is examined. Current literature on perphenazine's efficacy is also reviewed and discussed alongside its limitations.

The Incidence of Torsades de Pointes With Perioperative Triple Antiemetic Administration

BACKGROUND

The safety of triple antiemetic therapy consisting of ondansetron, haloperidol, and a steroid, to surgical patients is unknown.

OBJECTIVE

To determine the incidence of torsade de pointes (TdP) or death following perioperative administration of triple antiemetic therapy.

METHODS

A retrospective cohort study identified 19,874 patients who received 22,202 doses of triple antiemetics during the 2.5-year time frame from March 4, 2020 to September 7, 2022 for surgical nausea prophylaxis or treatment of nausea. These patients above were cross-matched with an electrocardiogram and adverse outcome database; this identified 226 patients with documentation of a QTc > 450 ms, all ventricular tachycardias including TdP within 48 hours of receiving triple antiemetic therapy, or death within 7 days of receiving ondansetron.

RESULTS

There were 3 patients who had documented VT (n = 3), but there were no documented incidents of TdP (n = 0). There were 9 codes called on patients within 48 hours of medication administration, and none of them were due to ventricular arrythmias (n = 0). A total of 11 patients died within 7 days of triple antiemetic therapy. Ten of the 11 deaths were determined to not be from the triple antiemetic. One patient died at home within 24 hours of the procedure of an unknown cause (n = 1).

CONCLUSIONS AND RELEVANCE

No episodes of TdP were identified in patients receiving triple antiemetic therapy perioperatively, though the cause of death in 1 patient could not be determined. This suggest that low-dose triple antiemetic therapy is low risk for the development of TdP.

Relationship of the 1846G > A Polymorphism of the CYP2D6 Gene to the Equilibrium Concentration Levels of Haloperidol in Patients with Acute Alcoholic Hallucinosis

Haloperidol is currently used in addictology for the treatment of acute psychotic disorders, including acute alcoholic hallucinosis. The use of haloperidol is often accompanied by the occurrence of adverse drug reactions (ADRs). There is evidence that CYP2D6 isoenzyme is involved in the biotransformation of haloperidol.

Aim

The study aimed to evaluate the relationship of 1846G > A polymorphism of the CYP2D6 gene to the equilibrium concentration levels of haloperidol in patients with acute alcoholic hallucinosis.

Material and Methods

The study was conducted on 100 male patients with acute alcoholic hallucinosis (mean age 41.4 ± 14.4 years). The efficacy profile was evaluated using the PANSS (Positive and Negative Syndrome Scale) scale. The safety of therapy was assessed using the UKU Side-Effect Rating Scale and the SAS (Simpson-Angus Scale for Extrapyramidal Symptoms) scale. Genotyping was performed using the real-time polymerase chain reaction (Real-time PCR). Equilibrium plasma concentration levels of haloperidol were investigated using the high-performance liquid chromatography with mass spectrometry (HPLC with MS/MS).

Results

No statistically significant results were obtained during the therapy efficacy assessment (dynamics of the PANSS score: GG genotype (-13.00 [-16.00; -16.00; -11.00]), GA genotype (-15.00 [-16.75; -13.00], p = 0.728). There was a statistically significant difference in safety assessment scores (dynamics of the UKU score: GG genotype (8.00 [7.00; 10.00]), GA genotype (15.00 [9.25; 18.00], p < 0.001); dynamics of the SAS score: GG genotype (11.00 [9.00; 14.00]), GA genotype (14.50 [12.00; 18.00], p < 0.001). The pharmacokinetic study results showed a statistically significant difference: GG (3.13 [2.32; 3.95]), GA (3.89 [2.92; 5.26], p = 0.010). Thus, a study conducted on a group of 100 patients with acute alcoholic hallucinosis demonstrated an association between the 1846G > A polymorphism of the CYP2D6 gene (rs3892097) and the safety profile of haloperidol therapy. We also revealed the presence of statistically significant difference in the equilibrium concentration levels of haloperidol in patients with the GG and AG genotypes.

Conclusion

It can be concluded that patients with the GA genotype have a higher risk of ADRs compared to patients carrying the GG genotype. It is shown that 1846G > A polymorphism of the CYP2D6 gene (rs3892097) has a statistically significant effect on the equilibrium concentration levels of haloperidol.

Relationship of CYP3A4*1B Single Nucleotide Polymorphism to the Efficiency and Safety Profiles of Haloperidol in Patients Enduring Acute Alcoholic Hallucinosis

To date, haloperidol has been widely used to treat patients with acute alcoholic hallucinosis. There is strong evidence that haloperidol therapy is commonly associated with adverse drug reactions (ADRs). The 392A > G polymorphism of the CYP3A4*1B gene (rs2740574) is known to affect the metabolism rates of haloperidol; hence it correlates with both therapy efficacy and safety parameters.

Objective

The study objective was to investigate the effect of 392A > G polymorphism of the CYP3A4*1B gene (rs2740574) on the efficacy and safety profiles of haloperidol in patients with acute alcoholic hallucinosis.

Methods

This study enrolled 100 male patients suffering from acute alcoholic hallucinosis (mean age 41.4 ± 14.4 years). The efficacy profile of haloperidol was assessed using the PANSS (Positive and Negative Syndrome Scale) validated psychometric scale. The safety profile of therapy was assessed with the UKU Side-Effect Rating Scale and the SAS (Simpson-Angus Scale for Extrapyramidal Symptoms) scale. Genotyping was performed using the real-time polymerase chain reaction (Real-time PCR).

Results

There were no statistically significant results for the efficacy rates (dynamics of the PANSS score: AA genotype -14.00 [-16.00; -12.00], AG genotype -13.00 [-14.00; -10.50], p = 0.306). Similarly, there was no statistically significant difference in the safety profiles (dynamics of the UKU score: AA genotype - 9.00 [7.00; 13.00], AG genotype - 8.50 [7.25; 10.50], p = 0.620; dynamics of the SAS score: AA genotype -12.00 [10.00; 16.75], AG genotype - 10.00 [10.00; 12.25], p = 0.321).

Conclusion

The study demonstrated that the 392A > G polymorphism of the CYP3A4*1B gene (rs2740574) in patients with acute alcoholic hallucinosis does not affect the efficacy and safety rates of haloperidol therapy.

Acute Extrapyramidal Side Effects Associated With the Combined Use of Low Doses of Haloperidol and Clarithromycin

Extrapyramidal side effects (EPS) are one of the major side effects that may frequently occur in the use of antipsychotics. EPS may cause distress and worsen the psychopathological condition. In this paper, we report a case of a 12-year-old boy with tic disorders who developed EPS after using haloperidol and clarithromycin combined.

Haloperidol alters neurotrophic factors and epigenetic parameters in an animal model of schizophrenia induced by ketamine

This study aimed to evaluate Haloperidol's (Hal) effects on the behavioral, neurotrophic factors, and epigenetic parameters in an animal model of schizophrenia (SCZ) induced by ketamine (Ket). Injections of Ket or saline were administered intraperitoneal (once a day) between the 1st and 14th days of the experiment. Water or Hal was administered via gavage between the 8th and 14th experimental days. Thirty minutes after the last injection, the animals were subjected to behavioral analysis. The activity of DNA methyltransferase (DNMT), histone deacetylase (HDAC), and histone acetyltransferase and levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and glial-derived neurotrophic factor (GDNF) were evaluated in the frontal cortex, hippocampus, and striatum. Ket increased the covered distance and time spent in the central area of the open field, and Hal did not reverse these behavioral alterations. Significant increases in the DNMT and HDAC activities were detected in the frontal cortex and striatum from rats that received Ket, Hal, or a combination thereof. Besides, Hal per se increased the activity of DNMT and HDAC in the hippocampus of rats. Hal per se or the association of Ket plus Hal decreased BDNF, NGF, NT-3, and GDNF, depending on the brain region and treatment regimen. The administration of Hal can alter the levels of neurotrophic factors and the activity of epigenetic enzymes, which can be a factor in the development of effect collateral in SCZ patients. However, the precise mechanisms involved in these alterations are still unclear.

Bacillus Calmette-Guérin Vaccine Attenuates Haloperidol-Induced TD-like Behavioral and Neurochemical Alteration in Experimental Rats

Tardive dyskinesia (TD) is a hyperkinetic movement disorder that displays unusual involuntary movement along with orofacial dysfunction. It is predominantly associated with the long-term use of antipsychotic medications, particularly typical or first-generation antipsychotic drugs such as haloperidol. Oxidative stress, mitochondrial dysfunction, neuroinflammation, and apoptosis are major pathophysiological mechanisms of TD. The BCG vaccine has been reported to suppress inflammation, oxidative stress, and apoptosis and exert neuroprotection via several mechanisms. Our study aimed to confirm the neuroprotective effect of the BCG vaccine against haloperidol-induced TD-like symptoms in rats. The rats were given haloperidol (1 mg/kg, i.p.) for 21 days after 1 h single administration of the BCG vaccine (2 × 107 cfu). Various behavioral parameters for orofacial dyskinesia and locomotor activity were assessed on the 14th and 21st days after haloperidol injection. On the 22nd day, all rats were euthanized, and the striatum was isolated to estimate the biochemical, apoptotic, inflammatory, and neurotransmitter levels. The administration of the BCG vaccine reversed orofacial dyskinesia and improved motor function in regard to haloperidol-induced TD-like symptoms in rats. The BCG vaccine also enhanced the levels of antioxidant enzymes (SOD, GSH) and reduced prooxidants (MDA, nitrite) and pro-apoptotic markers (Cas-3, Cas-6, Cas-9) in rat brains. Besides this, BCG treatment also restored the neurotransmitter (DA, NE, 5-HT) levels and decreased the levels of HVA in the striatum. The study findings suggest that the BCG vaccine has antioxidant, antiapoptotic, and neuromodulatory properties that could be relevant in the management of TD.

Acute Caudate Nucleus Stroke Presenting As Hemiballismus

Hemiballismus is defined as irregular, involuntary, large-amplitude flinging movements by the limbs, confined to one side of the body. Hemichorea refers to a state of excessive and irregularly timed, non-repetitive and randomly distributed, spontaneous, involuntary, and abrupt movements. It is widely believed that hemiballismus and chorea are suggestive of a lesion to the basal ganglia and subthalamic nucleus (STN). However, there are other etiologies that may influence the clinical presentation. Patients may present with certain common clinical features corresponding to the affected area of the brain. For example, infarctions of the motor cortex present with hemiplegia or paralysis of one side of the body. Similarly, infarctions involving the language areas of the brain present with aphasia and are detrimental to speech production or comprehension and the ability to read and write. Typically, acute-onset hemichorea is suggestive of a lesion in the STN. Herein, we present a rare case of acute hemiballismus and hemichorea following infarction of the left caudate nucleus, as determined by magnetic resonance imaging (MRI) and computerized tomography (CT) imaging modalities.

Perioperative utility of amisulpride and dopamine receptor antagonist antiemetics-a narrative review

Despite advances in antiemetics and protocolized postoperative nausea vomiting (PONV) management, it remains one of the most common postoperative adverse events. In patients who developed PONV despite antiemetic prophylaxis, giving a rescue treatment from the same class of medication is known to be of limited efficacy. Given the widespread use of 5-HT3 antagonists as PONV prophylaxis, another class of effective intravenous rescue antiemetic is in dire need, especially when prophylaxis fails, and rescue medication is utilized. Dopamine antagonists were widely used for the treatment of PONV but have fallen out of favor due to some of their side effect profiles. Amisulpride was first designed as an antipsychotic medication but was found to have antiemetic properties. Here we will review the historical perspective on the use of dopamine receptor antagonist antiemetics, as well as the evidence on the efficacy and safety of amisulpride.

Dose-dependent QTc interval prolongation under haloperidol and pipamperone in the management of delirium in a naturalistic setting

Objective

Delirium is an acute, life-threatening neuropsychiatric disorder frequently occurring among hospitalized patients. Antipsychotic medications are often recommended for delirium management but are associated with cardiovascular risks. This study aimed to investigate the frequency and magnitude of QTc interval prolongation and clinically relevant side effects occurring in delirium patients managed with haloperidol and/or pipamperone.

Methods

This descriptive retrospective cohort study evaluated 102 elderly (mean age: 73.2 years) inpatients with delirium treated with either haloperidol, pipamperone, a combination of both, or neither in a naturalistic setting over the course of up to 20 days or until the end of delirium.

Results

A total of 86.3% of patients were treated with haloperidol and/or pipamperone at a mean daily haloperidol-equipotent dose of 1.2 ± 1 mg. Non-cardiovascular side effects were registered in 2.9% of all patients and correlated with higher scores on the Delirium Observation Screening Scale. They did not occur more frequently under antipsychotic treatment. The frequency of QTc interval prolongation was comparably common among all groups, but prolongation magnitude was higher under antipsychotic treatment. It was positively correlated with antipsychotic dosage and the total number of QTc interval-prolonging substances administered. Critical QTc interval prolongation was registered in 21.6% (n = 19) of patients in the group treated with antipsychotics compared to 14.3% (n = 2) of patients in the unmedicated group; however, the difference was not statistically significant. Polypharmacy was associated with a higher risk of critical QTc interval prolongation and increased mortality during delirium.

Conclusion

Delirium treatment with haloperidol and/or pipamperone was not associated with a higher risk of QTc-interval prolongation in this naturalistic patient sample but was greater in magnitude and correlated with equipotent dosage and the number of QT interval-prolonging substances used. Polypharmacy was associated with higher mortality and increased risk of critical QTc prolongation.

Extrapyramidal Side Effects with Chronic Atypical Antipsychotic Can Be Predicted by Labeling Pattern of FosB and phosphoThr34-DARPP-32 in Nucleus Accumbens

Extrapyramidal side effects (EPS) can be induced by neuroleptics that regulate the expression of transcription factor FosB and dopaminergic mediator DARPP-32 in the striatum. However, the long-term neurobiological changes in striatal projection neurons resulting from a cumulative dosage of typical and atypical antipsychotics are poorly understood. The present study aimed to determine the differential and long-lasting changes in FosB distribution and DARPP-32 phosphorylation in the striatum and nucleus accumbens (NAc) associated with chronic antipsychotic-induced EPS. Male C57Bl/6J mice received daily injections of Olanzapine (Olz, 15 mg/kg), Clozapine (Clz, 20 mg/kg), or Haloperidol (Hal, 1 mg/kg), for a period of 11 weeks with a 4-day withdrawal period before the last dosage. Catalepsy for detection of EPS, along with open-field and rotarod tests, were assessed as behavioral correlates of motor responses. Additionally, FosB and phosphorylated-DARPP-32 immunohistochemistry were examined in striatal regions after treatment. All antipsychotics produced catalepsy and reduced open-field exploration, such as impaired rota-rod performance after Olz and Hal. The washout period was critical for Clz-induced side effects reduction. Both Olz and Clz increased FosB in NAc Shell-region, and phosphoThr34-DARPP-32 in NAc. Only Clz reduced phosphoThr75-DARPP-32 in the dorsal striatum and showed FosB/phosphoThr34-Darpp-32-ir in the NAc Core region. This study provides evidence that atypical antipsychotics such as Olz and Clz also give rise to EPS effects frequently associated with a cumulative dosage of typical neuroleptics such as Hal. Nevertheless, FosB/phosphoThr34-Darpp-32-ir in the NAc Core region is associated with hypokinetic movements inhibition.

Stimulatory and inhibitory effect of antipsychotic agents including dopaminergic neuro-depressants on dopamine formation from p-tyramine mediated by cytochrome P450 2D6

BACKGROUND AND OBJECTIVES

The effects of antipsychotic agents, including dopamine D2 receptor blocking agents such as haloperidol, chlorpromazine, and sulpiride, and related compounds such as mirtazapine and sertraline, on dopamine formation from p-tyramine catalyzed by cytochrome P450 (CYP) 2D6.2 (Arg296Cys;Ser486Thr), CYP2D6.10 (Pro34Ser;Ser486Thr), and CYP2D6.39 (Ser486Thr) were compared with those of CYP2D6.1.

METHODS

Dopamine was determined by high-performance liquid chromatography, and Michaelis constants (Km), maximal velocity (kcat) values for dopamine formation, and inhibition constants (Ki) of psychotropic agents were estimated.

RESULTS

Km values for all CYP2D6 variants decreased at lower concentrations, and kcat values for CYP2D6 variants except for CYP2D6.10 gradually increased with increasing haloperidol concentrations up to 5 or 10 μM. The kcat/Km values for all CYP2D6 variants increased at under 2.5 μM concentrations. Lower sertraline concentrations decreased Km values for CYP2D6.10. Chlorpromazine at concentrations under 10 µM competitively inhibited the activities catalyzed by all variants; however, the activities for only CYP2D6.10 were increased by chlorpromazine at concentrations over 250 µM. Mirtazapine and sertraline similarly decreased dopamine formation among all variants except for CYP2D6.10. However, CYP2D6.10 inhibition by mirtazapine was weaker than that of the other variants, and sertraline decreased Km values for CYP2D6.10.

CONCLUSION

Haloperidol and sertraline, but not sulpiride, decreased the Km and/or increased kcat values for CYP2D6. The present findings suggest that Dopamine D2 receptor-blocking agents and related compounds may polymorphically affect dopamine formation catalyzed by CYP2D6 in the brain.

Switching to long-acting injectable antipsychotics: pharmacological considerations and practical approaches

INTRODUCTION

Long-acting injectable antipsychotics (LAIs) are an effective, but potentially underutilized treatment option in schizophrenia and other severe mental illnesses. Prescribing information typically focuses on how to initiate treatment from the corresponding oral formulations. However, in clinical practice other scenarios, such as switching from other oral antipsychotics or other LAIs, occur frequently, requiring guidance.

AREAS COVERED

Pharmacodynamic properties of antipsychotics and their relation to rebound symptoms. Pharmacokinetic properties of LAIs and their implications for switching approaches. Specific approaches to switching to LAIs.

EXPERT OPINION

The LAI landscape has evolved significantly in the last decade with more formulations available, longer dosing intervals, and extended indications. However, currently available LAIs have various shortcomings, e.g. short dosing intervals, need for oral supplementation, loading regimens, deep intramuscular injection and/or restricted indications. Recent improvements include a one-day initiation option for aripiprazole lauroxil, aripiprazole monohydrate once-monthly, risperidone in situ microparticles and subcutaneous risperidone. Future LAI developments should focus on longer dosing intervals, subcutaneous administration, expansion of LAIs beyond currently available antipsychotic agents and indications beyond schizophrenia and bipolar disorder. In the future, LAIs might become a first-line treatment after initial oral stabilization for chronic mental disorders with need for maintenance treatment and presence of significant non-adherence.

Investigating the Use of Pharmacogenetic and Pharmacometabolomic Markers to Predict Haloperidol Efficacy and Safety Rates

Background: Haloperidol is commonly prescribed to patients with alcohol-induced psychotic disorder (AIPD). Notably however, individuals differ extensively with regards to therapeutic response and adverse drug reactions (ADRs). Previous studies have shown that haloperidol biotransformation is mainly metabolized by CYP2D6. Objective: The objective of our study was to investigate the use of pharmacogenetic (CYP2D6*4 genetic polymorphism) and pharmacometabolomic biomarkers to predict haloperidol efficacy and safety rates. Material and Methods: The study enrolled 150 patients with AIPD. Therapy included haloperidol in a daily dose of 5 to 10 mg/day by injections for 5 days. Efficacy and safety of treatment were evaluated using the validated psychometric scales PANSS, UKU, and SAS. Results: No association of the urinary 6-НО-ТНВС/pinoline ratio values which could be evidence of the CYP2D6 activity level with both the efficacy and safety rates of haloperidol was demonstrated. However, a statistically significant association between haloperidol safety profile and CYP2D6*4 genetic polymorphism was demonstrated (P < .001). Conclusion: To predict haloperidol efficacy and safety rates, utilization of pharmacogenetic testing that defines CYP2D6*4 genetic polymorphism is found preferable over the use of the pharmacometabolomic marker in a clinical setting.

The efficacy and safety of haloperidol for the treatment of delirium in critically ill patients: a systematic review and meta-analysis of randomized controlled trials

Purpose

Delirium is common during critical illness and is associated with poor outcomes. Therefore, we conducted this meta-analysis to investigate the efficacy and safety of haloperidol for the treatment of delirium in critically ill patients.

Methods

Randomized controlled trials enrolling critically ill adult patients to compare haloperidol with placebo were searched from inception through to February 20th, 2023. The primary outcome were delirium-free days and overall mortality, secondary outcomes were length of intensive care unit stay, length of hospital stay, and adverse events.

Results

Nine trials were included in our meta-analysis, with a total of 3,916 critically ill patients. Overall, the pooled analyses showed no significant difference between critically ill patients treated with haloperidol and placebo for the delirium-free days (MD -0.01, 95%CI -0.36 to 0.34, p = 0.95, I2 = 30%), overall mortality (OR 0.89, 95%CI 0.76 to 1.04, p = 0.14, I2 = 0%), length of intensive care unit stay (MD -0.06, 95%CI -0.16 to 0.03, p = 0.19, I2 = 0%), length of hospital stay (MD -0.06, 95%CI -0.61 to 0.49, p = 0.83, I2 = 0%), and adverse events (OR 0.90, 95%CI 0.60 to 1.37, p = 0.63, I2 = 0%).

Conclusion

Among critically ill patients, the use of haloperidol as compared to placebo has no significant effect on delirium-free days, overall mortality, length of intensive care unit and/or hospital stay. Moreover, the use of haloperidol did not increase the risk of adverse events.

Haloperidol versus Second-generation Antipsychotics on the cognitive performance of individuals with schizophrenia and related disorders: pairwise meta-analysis of randomized controlled trials

INTRODUCTION

Despite previous literature, the superiority of Second-generation Antipsychotics (SGAs) relative to First-generation Antipsychotics- especially haloperidol - on cognitive management in schizophrenia is still controversial. Thus, we aimed to compare the effects of haloperidol versus SGAs on the cognitive performance of individuals with schizophrenia or related disorders.

METHODS

We conducted an updated systematic review and nine pairwise meta-analyses of double-blinded randomized controlled trials published up to October 30th, 2022, using Medline, Web of Science, and Embase.

RESULTS

Twenty-eight trials were included, enrolling 1,932 individuals. Compared to SGAs, haloperidol performed worse on cognitive composite (MD -0.13; 95% CI: -0.33 to -0.03; MD = mean difference, CI = confidence interval), processing speed (MD -0.17; 95% CI: -0.28 to -0.07), attention (MD -0.14; 95% CI: -0.26 to -0.02), motor performance (MD -0.17; 95% CI: -0.31 to -0.03), memory and verbal learning (MD -0.21; 95% CI: -0.35 to -0.08), and executive function (MD -0.27; 95% CI: -0.43 to -0.11). In contrast, there were no significant differences between SGAs and haloperidol on working memory (MD 0.10; 95% CI: -0.08 to 0.27), visual learning (MD 0.08; 95% CI: -0.05 to 0.21), social cognition (MD 0.29; 95% CI: -0.30 to 0.88), and visuoconstruction (MD 0.17; 95% CI: -0.04 to 0.39).

CONCLUSION

Haloperidol had poorer performance in global cognition and in some cognitive domains, but with small effect sizes. Therefore, it was not possible to conclude that haloperidol is certainly worse than SGAs in the long-term cognitive management of schizophrenia.

Involvement of Antioxidant and Prevention of Mitochondrial Dysfunction, Anti-Neuroinflammatory Effect and Anti-Apoptotic Effect: Betaine Ameliorates Haloperidol-Induced Orofacial Dyskinesia in Rats

With its pathophysiological characteristics strongly similar to patients with tardive dyskinesia (TD), haloperidol (HP)-induced neurotoxicity and orofacial dyskinesia (OD) in animal models have long been used to study human TD. This study aimed to explore the potential protective effects of betaine (BT), a vital biochemical compound present in plants, microorganisms, animals, and various dietary sources. The study focused on investigating the impact of BT on haloperidol (HP)-induced orofacial dyskinesia (OD) in rats, as well as the underlying neuroprotective mechanisms. To induce the development of OD, which is characterized by increased vacuous chewing movement (VCM) and tongue protrusion (TP), rats were administered HP (1 mg/kg i.p.) for 21 consecutive days. BT was administered intraperitoneally (i.p.) at doses of 30 and 100 mg/kg, 60 min later, for 21 successive days. On the 21st day, after evaluating OD behavior, the rats were sacrificed, and various measurements were taken to assess the nitrosative and oxidative status, antioxidant capacity, mitochondrial function, neuroinflammation, and apoptotic markers in the striatum. The results demonstrated that (1) HP induced OD development, and (2) BT was found to prevent most of the HP-induced OD; decrease oxidative stress levels; increase anti-oxidation power; prevent mitochondrial dysfunction; and reduce the levels of neuroinflammatory and apoptotic markers in the striatum. Our results demonstrate that the neuroprotective effects of BT against HP-induced OD are credited to its antioxidant prevention of mitochondrial dysfunction, anti-neuroinflammatory effects, and anti-apoptotic effects, suggesting that BT may be a novel therapeutic candidate in delaying or treating human TD in clinical settings. However, further studies will be warranted to extrapolate preclinical findings into clinical studies for a better understanding of the role of BT.

Haloperidol's Cytogenetic Effect on T Lymphocytes of Systemic Lupus Erythematosus and Rheumatoid Arthritis Patients: An In Vitro Study

OBJECTIVES

Investigating haloperidol's cytogenetic behavior in cultured human T lymphocytes of patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).

METHODS

Four haloperidol solutions were added in cultures of peripheral blood lymphocytes of healthy individuals, SLE, and RA patients. After 72 hours of incubation, the cultured lymphocytes were plated on glass slides, and stained with the fluorescence plus Giemsa method, and sister chromatid exchanges (SCEs), proliferation rate index (PRI), and mitotic index (MI) were measured with the optical microscope.

RESULTS

Result analysis revealed: (a) a statistically significant (p=0.001) dose-dependent increase of SCEs in SLE patients compared to healthy individuals; (b) a statistically significant (p=0.001) dose-dependent decrease of SCEs in RA patients for haloperidol concentrations 5, 10μg/mL; (c) a statistically significant (p=0.001) dose-dependent increase of SCEs in RA patients for haloperidol concentrations 20, 100μg/mL; and (d) a statistically significant (p=0.001) dose-dependent reduction of PRI and MI in both patient groups compared to healthy individuals. Furthermore, a correlation was observed between (a) SCE and PRI index variations, (b) MI and SCE index variations, and (c) PRI and MI index variations.

CONCLUSIONS

Haloperidol affects T lymphocytes from SLE and RA patients by modifying DNA replication procedures, DNA damage response, and ferroptosis. Considering the wide use of haloperidol in neuropsychiatric symptoms of SLE and RA patients, further studies with more immune cell subsets are needed to evaluate its effects on human genetic material.

Extensive Soft Tissue Swelling in the Larynx and Hypopharynx of a Young Female Patient After Haloperidol Use: A Case Report on Angioneurotic Edema

Angioneurotic edema is a potentially life-threatening condition characterized by the rapid swelling of subcutaneous and submucosal tissues of the upper respiratory and gastrointestinal tracts. It may result in laryngeal edema, thus obstructing the airway, with a potentially fatal outcome if not diagnosed early. An allergic reaction typically causes it, but certain drugs can induce or contribute to the development of angioneurotic edema in rare cases. Haloperidol is one of the most commonly used antipsychotics to treat psychiatric disorders such as schizophrenia and, in the emergency room, acute delirium and acute psychosis. While it is generally well tolerated, in rare cases, individuals may experience a severe reaction in response to haloperidol administration. Here, we present the case of angioneurotic edema associated with intramuscular haloperidol use in a 29-year-old female patient with a history of bipolar disorder and no previous history of allergy. This case report aims to raise awareness among clinicians about this rare adverse reaction associated with haloperidol use.

SAEM GRACE: Dopamine antagonists and topical capsaicin for cannabis hyperemesis syndrome in the emergency department: A systematic review of direct evidence

BACKGROUND

Adults with cannabis hyperemesis syndrome (CHS) are increasingly presenting to the emergency department (ED), and this systematic review will evaluate the direct evidence on the effectiveness of capsaicin and dopamine antagonists in its clinical management.

METHODS

A bibliographic search was conducted to address the following population-intervention-control-outcome (PICO) question: (P) adults >18 years old with a diagnosis of acute CHS presenting to the ED; (I) dopamine antagonists (e.g., haloperidol, droperidol) and topical capsaicin; (C) usual care or no active comparator; and (O) symptoms improvement/resolution in ED, ED length of stay, admission rate, ED recidivism, need for rescue medication, and adverse events. This systematic review was conducted in accordance with PRISMA reporting recommendations.

RESULTS

From 53 potentially relevant articles, seven articles were included: five observational studies and two randomized controlled trials, including a total of 492 patients. Five of these studies evaluated the efficacy of capsaicin cream (n = 386), and two examined dopamine antagonists (haloperidol, droperidol; n = 106). There was mixed evidence for the efficacy of capsaicin for reducing nausea and emesis. Both studies evaluating dopamine antagonists detected clinical benefit to usual care or no active comparator.

CONCLUSIONS

There is limited direct evidence on the efficacy of dopamine antagonists or capsaicin for treating CHS in the ED. Current evidence is mixed for capsaicin and potentially beneficial for dopamine antagonists. Because of the small number of studies, small number of participants, lack of standardization of treatment administration, and risk of bias of the included studies, methodologically rigorous trials on both types of intervention are needed to directly inform ED management of CHS.

Characterizing PRN Use of Psychotropic Medications for Acute Agitation in Canadian Long-Term Care Residents with Dementia Before and During COVID-19

Background

Agitation is a disabling neuropsychiatric symptom of dementia. Pro re nata (PRN) injections of psychotropics can be administered for severe acute agitation, but little is known about the frequency of their actual use.

Objective

Characterize actual use of injectable PRN psychotropics for severe acute agitation in Canadian long-term care (LTC) residents with dementia and compare use before and during the COVID-19 pandemic.

Methods

Residents from two Canadian LTC facilities with orders for PRN haloperidol, olanzapine, or lorazepam between January 1, 2018- May 1, 2019 (i.e., pre-COVID-19) and January 1, 2020- May 1, 2021 (i.e., COVID-19) were identified. Electronic medical records were reviewed to document PRN injections of psychotropic medications and collect data on reason and demographic characteristics. Descriptive statistics were used to characterize frequency, dose, and indications of use, and multivariate regression models were used to compare use between time periods.

Results

Of the 250 residents, 45 of 103 (44%) people in the pre-COVID-19 period and 85 of 147 (58%) people in the COVID-19 period with standing orders for PRN psychotropics received ≥1 injections. Haloperidol was the most frequently used agent in both time periods (74% (155/209 injections) pre-COVID-19; 81% (323/398 injections) during COVID-19). Residents in the COVID-19 period were almost two times more likely to receive injections compared with those in the pre-COVID-19 period (odds ratio = 1.96; 95% CI = 1.15-3.34; p = 0.01).

Conclusion

Our results suggest that use of PRN injections increased in LTC during the pandemic and contribute to the mounting evidence that agitation worsened during that time.

The ANKK1/DRD2 gene TaqIA polymorphism (rs1800497) is associated with the severity of extrapyramidal side effects of haloperidol treatment in CYP2D6 extensive metabolizers with schizophrenia spectrum disorders

OBJECTIVES

Extrapyramidal symptoms (EPS) are one of the most prominent side effects of haloperidol. Variability of EPS severity may be associated with the genetic factors, affecting both haloperidol pharmacokinetics (e.g., CYP2D6) and pharmacodynamics (e.g., DRD2, ANKK1). We conducted a 3-week prospective study to investigate the associations of ANKK1/DRD2 TaqIA (rs1800497), DRD2 -141C Ins/Del (rs1799732) polymorphisms and CYP2D6 metabolic phenotype on the efficacy of haloperidol treatment and severity of EPS in patients with schizophrenia spectrum disorders.

METHODS

In total, 57 inpatients with schizophrenia spectrum disorders (24 (42.1%)) females; age -46.7 (11.8) years (M(SD)) of European ancestry were enrolled. BARS and SAS scales were used to assess EPS. PANSS and CGI scales - to assess the efficacy of haloperidol treatment. Genotyping was performed by real-time PCR. CYP2D6 metabolic phenotype was predicted by the CYP2D6 *3, *4, *5, *6, *9, *10, *41 and xN genotypes.

RESULTS

Minor C allele of TaqIA was associated with higher scores of BARS (p=0.029) and SAS (p=0.024) on day 21 and minor Del allele of -141C Ins/Del - with more prominent clinical improvement by CGI scale (p=0.007) but not by PANSS. These differences were observed only in extensive CYP2D6 metabolizers, although no associations with the metabolic type itself were found. General linear model showed that the combination of TaqIA genotype and metabolic type was significantly associated with BARS score on day 21 (p=0.013).

CONCLUSIONS

Our results highlight the importance of using both pharmacokinetic and pharmacodynamic genetic markers for predicting haloperidol treatment response to personalize schizophrenia spectrum disorders treatment.

Second-Generation Parenteral Antipsychotic (Olanzapine) as a First-Line Treatment for Acute Undifferentiated Agitation in the Emergency Department in Comparison With Haloperidol

Background Acutely agitated patients are common in the emergency department (ED). Given the myriad aetiologies of the clinical conditions that can produce agitation, such a high prevalence is unsurprising. Agitation is a symptomatic presentation, not a diagnosis, secondary to a psychiatric, medical, traumatic, or toxicological condition. Most literature on the emergency management of agitated patients is from psychiatric populations, not generalised to EDs. Benzodiazepines, antipsychotics, and ketamine have been used to treat acute agitation. However, a clear consensus is lacking. Objectives The objectives are to study the effectiveness of intramuscular (IM) olanzapine as a first-line treatment for rapid tranquillisation in undifferentiated acute agitation in the ED and compare the effectiveness of sedatives to control agitation in etiologically divided groups per the following preassigned protocols: Group A: Alcohol/drug intoxication (olanzapine vs haloperidol), Group B: Traumatic brain injury (TBI) with or without alcohol intoxication (olanzapine vs haloperidol), Group C: Psychiatric conditions (olanzapine vs haloperidol and lorazepam), and Group D: Agitated delirium, organic causes (olanzapine vs haloperidol). Methods This 18-month prospective study included acutely agitated ED patients between 18 and 65. Results A total of 87 patients between 19 and 65 were included, all with a Richmond Agitation Sedation Scale (RASS) score between +2 and +4 at presentation. Nineteen of the 87 patients were managed as acute undifferentiated agitation, and 68 were assigned to one of the four groups. In acute undifferentiated agitation, IM olanzapine 10 mg effectively sedated 15 (78.9%) patients within 20 minutes, whereas the remaining four (21.1%) were sedated with a repeat IM olanzapine 10 mg over the next 25 minutes. In 13 patients with agitation due to alcohol intoxication, zero out of three with olanzapine and four out of 10 (40%) with IM haloperidol 5 mg were sedated within 20 minutes. In patients with TBI, two out of eight (25%) receiving olanzapine and four out of nine (44.4%) receiving haloperidol were sedated within 20 minutes. In acute agitation secondary to psychiatric disease, olanzapine sedated nine out of 10 (90%), and haloperidol with lorazepam sedated 16 out of 17 (94.1%) within 20 minutes. In patients with agitation secondary to organic medical conditions, olanzapine rapidly sedated 19 out of 24 (79.1%), whereas haloperidol sedated one out of four (25%). Interpretation and conclusion IM olanzapine 10 mg is effective for rapid sedation in acute undifferentiated agitation. Olanzapine is superior to haloperidol in agitation secondary to organic medical conditions and is as efficacious as haloperidol with lorazepam in agitation due to psychiatric diseases. However, in agitation due to alcohol intoxication and TBI, haloperidol 5 mg is slightly better, although not statistically significant. Olanzapine and haloperidol were well tolerated by Indian patients in the current study, with minimal side effects.

Development of a Novel σ1 Receptor Biosensor Based on Its Heterodimerization with Binding Immunoglobulin Protein in Living Cells

The σ₁ receptor (S1R) is a ligand-regulated non-opioid intracellular receptor involved in several pathological conditions. The development of S1R-based drugs as therapeutic agents is a challenge due to the lack of simple functional assays to identify and classify S1R ligands. We have developed a novel nanoluciferase binary technology (NanoBiT) assay based on the ability of S1R to heteromerize with the binding immunoglobulin protein (BiP) in living cells. The S1R-BiP heterodimerization biosensor allows for rapid and accurate identification of S1R ligands by monitoring the dynamics of association-dissociation of S1R and BiP. Acute treatment of cells with the S1R agonist PRE-084 produced rapid and transient dissociation of the S1R-BiP heterodimer, which was blocked by haloperidol. The effect of PRE-084 was enhanced by calcium depletion, leading to a higher reduction in heterodimerization even in the presence of haloperidol. Prolonged incubation of cells with S1R antagonists (haloperidol, NE-100, BD-1047, and PD-144418) increased the formation of S1R-BiP heteromers, while agonists (PRE-084, 4-IBP, and pentazocine) did not alter heterodimerization under the same experimental conditions. The newly developed S1R-BiP biosensor is a simple and effective tool for exploring S1R pharmacology in an easy cellular setting. This biosensor is suitable for high-throughput applications and a valuable resource in the researcher's toolkit.

The Effects of Antipsychotics in Experimental Models of Krabbe Disease

The role of altered myelin in the onset and development of schizophrenia and changes in myelin due to antipsychotics remains unclear. Antipsychotics are D₂ receptor antagonists, yet D₂ receptor agonists increase oligodendrocyte progenitor numbers and limit oligodendrocyte injury. Conflicting studies suggest these drugs promote the differentiation of neural progenitors to oligodendrocyte lineage, while others report antipsychotics inhibit the proliferation and differentiation of oligodendrocyte precursors. Here, we utilised in-vitro (human astrocytes), ex-vivo (organotypic slice cultures) and in-vivo (twitcher mouse model) experimental study designs of psychosine-induced demyelination, a toxin that accumulates in Krabbe disease (KD), to investigate direct effects of antipsychotics on glial cell dysfunction and demyelination. Typical and atypical antipsychotics, and selective D₂ and 5HT_2A receptor antagonists, attenuated psychosine-induced cell viability, toxicity, and morphological aberrations in human astrocyte cultures. Haloperidol and clozapine reduced psychosine-induced demyelination in mouse organotypic cerebellar slices. These drugs also attenuated the effects of psychosine on astrocytes and microglia and restored non-phosphorylated neurofilament levels, indicating neuroprotective effects. In the demyelinating twitcher mouse model of KD, haloperidol improved mobility and significantly increased the survival of these animals. Overall, this study suggests that antipsychotics directly regulate glial cell dysfunction and exert a protective effect on myelin loss. This work also points toward the potential use of these pharmacological agents in KD.

Drug Repurposing in Pediatric Brain Tumors: Posterior Fossa Ependymoma and Diffuse Midline Glioma under the Looking Glass

Tumors of the Central Nervous System (CNS) represent the leading cause of cancer-related deaths in children. Current treatment options are not curative for most malignant histologies, and intense preclinical and clinical research is needed to develop more effective therapeutic interventions against these tumors, most of which meet the FDA definition for orphan diseases. Increased attention is being paid to the repositioning of already-approved drugs for new anticancer indications as a fast-tracking strategy for identifying new and more effective therapies. Two pediatric CNS tumors, posterior fossa ependymoma (EPN-PF) type A and diffuse midline glioma (DMG) H3K27-altered, share loss of H3K27 trimethylation as a common epigenetic hallmark and display early onset and poor prognosis. These features suggest a potentially common druggable vulnerability. Successful treatment of these CNS tumors raises several challenges due to the location of tumors, chemoresistance, drug blood-brain barrier penetration, and the likelihood of adverse side effects. Recently, increasing evidence demonstrates intense interactions between tumor cell subpopulations and supportive tumor microenvironments (TMEs) including nerve, metabolic, and inflammatory TMEs. These findings suggest the use of drugs, and/or multi-drug combinations, that attack both tumor cells and the TME simultaneously. In this work, we present an overview of the existing evidence concerning the most preclinically validated noncancer drugs with antineoplastic activity. These drugs belong to four pharmacotherapeutic classes: antiparasitic, neuroactive, metabolic, and anti-inflammatory. Preclinical evidence and undergoing clinical trials in patients with brain tumors, with special emphasis on pediatric EPN-PF and DMG, are summarized and critically discussed.

Intravenous haloperidol and cocaine alter the distribution of T CD3+ CD4+ , non-T/NK and NKT cells in rats

The modulation of dopamine transmission evokes strong behavioural effects that can be achieved by commonly used psychoactive drugs such as haloperidol or cocaine. Cocaine non-specifically increases dopamine transmission by blocking dopamine active transporter (DAT) and evokes behavioural arousal, whereas haloperidol is a non-specific D2-like dopamine receptor antagonist with sedative effects. Interestingly, dopamine has been found to affect immune cells in addition to its action in the central nervous system. Here, we address the possible interactions between haloperidol and cocaine and their effects on both immune cells and behaviour in freely moving rats. We use an intravenous model of haloperidol and binge cocaine administration to evaluate the drugs' impact on the distribution of lymphocyte subsets in both the peripheral blood and the spleen. We assess the drugs' behavioural effects by measuring locomotor activity. Cocaine evoked a pronounced locomotor response and stereotypic behaviours, both of which were completely blocked after pretreatment with haloperidol. The results suggest that blood lymphopenia, which was induced by haloperidol and cocaine (except for natural killer T cells), is independent of D2-like dopaminergic activity and most likely results from the massive secretion of corticosterone. Haloperidol pretreatment prevented the cocaine-induced decrease in NKT cell numbers. Moreover, the increased systemic D2-like dopaminergic activity after cocaine administration is a significant factor in retaining T CD3⁺ CD4⁺ lymphocytes and non-T/NK CD45RA⁺ cells in the spleen.

Visualizing How to Use Antipsychotics for Agitated Delirium in the Last Days of Life

CONTEXT

How physicians use antipsychotics for agitated delirium in the last days of life varies markedly, which could hamper the quality of care.

OBJECTIVES

To examine adherence to an algorithm-based treatment for terminal agitated delirium, and explore its effectiveness and safety.

METHODS

A single-center, prospective, observational study was conducted in a 27-bed palliative care unit in Japan. All adult cancer patients who developed agitated delirium with a modified Richmond Agitation-Sedation Scale (RASS) of +1 or more were included; the palliative care specialists determined that the etiology was irreversible, the estimated survival was three weeks or less, and the Eastern Cooperative Oncology Group (ECOG) performance status was three or four. Patients were treated with an algorithm to visualize how to use antipsychotics, with the treatment goal defined as no agitation (RASS≤0) or acceptable agitation for patients and families. We provided all patients nonpharmacological management to alleviate the symptoms of delirium and administered antipsychotic medications when the nonpharmacological approach was insufficient. We measured the adherence rate, RASS, Nursing Delirium Screening Scale items 2, 3, 4 (Nu-DESC), and Agitation Distress Scale item 2 (ADS) on days 0, 1, 3, 7, 14, 21, and 24 hours before death.

RESULTS

A total of 164 patients were enrolled. Adherence rates were 99, 94, and 89%, and treatment goals were achieved in 66, 83, and 93% on days one, three, and seven, respectively. The mean RASS decreased from +1.41 to -0.84 on day three; Nu-DESC decreased from 4.19 to 1.83, and ADS decreased from 1.54 to 0.38. There were seven severe adverse events (Common Terminology Criteria for Adverse Events (CTCAE) of 3), including aspiration (n = 3), apnea (n = 2), tremor (n = 1), and muscle rigidity (n = 1) on day three.

CONCLUSION

The algorithm-based treatment could be feasible, effective, and safe. Visualizing how palliative care specialists provide pharmacological management could be beneficial for nonspecialist clinicians, and clinical, educational, and research implications warrant further empirical testing.

Effects of antipsychotics, haloperidol and olanzapine, on the expression of apoptosis-related genes in mouse mHippoE-2 cells and rat hippocampus

Objective. Modified levels of pro- (caspase3, Bax) and anti-apoptotic (Bcl-2) regulatory proteins have been detected in certain brain areas of schizophrenic patients indicating a possible dysregulation of apoptosis. In the present study, effects of antipsychotics, haloperidol (HAL) and olanzapine (OLA), on the gene expression of caspase3 (casp3), Bax and Bcl-2 were studied in vitro in mouse hippocampal mHippoE-2 cell line and in vivo in the hippocampus of MK-801 animal schizophrenia model with the aim to provide evidence that antipsychotics may affect the activity of apoptosis-related markers. Methods. mHippoE-2 cells were incubated with MK-801 (20 µM), HAL (10 µM), and OLA (10 µM) alone or combined, MK-801+HAL/OLA, for 24, 48, and 72 h. Male Sprague Dawley rats were injected with saline or MK-801 (0.5 mg/kg) for 6 days and since the 7th day, they were treated with vehicle (VEH), HAL (1 mg/kg) or OLA (2 mg/kg) for the next 7 days. The casp3, Bax and Bcl-2 gene expression in mHippoE-2 cells and rat hippocampus was measured by RT-PCR. Results. In mHippoE-2 cells, casp3 gene expression was increased by MK-801 and OLA treatments alone for 48 h, HAL treatment alone for 24 and 72 h, and co-treatment with MK-801+OLA for 24 and 72 h compared to controls. HAL and OLA suppressed the stimulatory effect of MK-801 on casp3 mRNA levels in cells after 48 h of incubation. Bax mRNA levels in mHippoE-2 cells were decreased after HAL treatment for 24 and 48 h, and also after co-treatment with MK-801+HAL for 72 h. In vivo, MK-801 decreased mRNA levels of both pro-apoptotic markers, casp3 and Bax, in hippocampus of VEH-treated rats and Bax mRNA levels in hippocampus of HAL-treated animals. OLA reversed the inhibitory effect of MK-801 on casp3 expression in the VEH-treated animals. Neither MK-801 nor antipsychotics induced changes in the gene expression of anti-apoptotic marker Bcl-2 in mHippoE-2 cells as well as hippocampus of rats. Conclusions. The results of the present study demonstrate that antipsychotics, HAL and OLA, may affect mRNA levels of pro-apoptotic markers in hippocampal cells in vitro, but not in vivo. The obtained data do not clearly support the assumed potentiating role of MK-801 in inducing apoptosis in specific brain areas and a possible protective role of antipsychotics against induction of apoptosis. The obtained data may contribute to a deeper insight into the neurodevelopmental changes connected with schizophrenia.

A retrospective analysis of complications associated with postpartum hemorrhage up to 1 year postpartum in mothers with and without a pre-existing mental health diagnosis

BACKGROUND/OBJECTIVES

There is limited research on the associated immediate and long-term outcomes of postpartum hemorrhage. Mothers with a pre-existing psychiatric disease prior to delivery may be especially vulnerable to postpartum hemorrhage outcomes but little is known on this topic. Barriers to studying this population exist and add to knowledge gaps. The goal of this study is to determine the clinical characteristics and frequency of complications within 1 year of a postpartum hemorrhage diagnosis and the psychiatric sequelae within 7 days of a postpartum hemorrhage diagnosis in mothers with a pre-existing mental health diagnosis prior to delivery versus those without.

METHODS/DESIGN

This is a multicenter retrospective observational cohort study using TriNetX, a de-identified electronic health record database. The following electronic health record data were collected and evaluated in postpartum females who were billed for either a vaginal or cesarean delivery: age, race, ethnicity, diagnostic codes, medication codes, and number of deaths.

RESULTS

We included 10,649 subjects (6994 (65.7%) no mental health diagnosis and 3655 (34.3%) pre-existing mental health diagnosis). Haloperidol administration (118 (3.2%) versus 129 (1.8%), p < 0.001) was more prevalent in subjects with a pre-existing mental health diagnosis. Adjusting for demographics, pre-existing mental health diagnoses were associated with complications within 1 year after postpartum hemorrhage diagnosis (OR = 1.39, 95% CI: 1.26-1.52, p < 0.001).

CONCLUSION

Having a mental health disorder history is associated with a higher odds of developing subsequent complications within 1 year of postpartum hemorrhage diagnosis. Mothers with a pre-existing mental health disorder have a significantly higher frequency of certain severe postpartum hemorrhage sequelae, including acute respiratory distress syndrome, retained placenta, sickle cell crisis, and need for mechanical ventilation/tracheostomy up to 1 year after delivery. Medications such as haloperidol were ordered more frequently within 7 days of a postpartum hemorrhage diagnosis in these mothers as well. Further research is needed to understand and manage the unique consequences of postpartum hemorrhage in this vulnerable maternal population.

SLC6A3, HTR2C and HTR6 Gene Polymorphisms and the Risk of Haloperidol-Induced Parkinsonism

Antipsychotic-induced parkinsonism (AIP) is the most common type of extrapyramidal side effect (EPS), caused by the blockage of dopamine receptors. Since dopamine availability might influence the AIP risk, the dopamine transporter (DAT) and serotonin receptors (5-HTRs), which modulate the dopamine release, may be also involved in the AIP development. As some of the individual differences in the susceptibility to AIP might be due to the genetic background, this study aimed to examine the associations of SLC6A3, HTR2C and HTR6 gene polymorphisms with AIP in haloperidol-treated schizophrenia patients. The Extrapyramidal Symptom Rating Scale (ESRS) was used to evaluate AIP as a separate entity. Genotyping was performed using a PCR, following the extraction of blood DNA. The results revealed significant associations between HTR6 rs1805054 polymorphism and haloperidol-induced tremor and rigidity. Additionally, the findings indicated a combined effect of HTR6 T and SLC6A3 9R alleles on AIP, with their combination associated with significantly lower scores of ESRS subscale II for parkinsonism, ESRS-based tremor or hyperkinesia and ESRS subscales VI and VIII. These genetic predictors of AIP could be helpful in better understanding its pathophysiology, recognizing the individuals at risk of developing AIP and offering personalized therapeutic strategies for the patients suffering from this EPS.

Pupillary dynamics of mice performing a Pavlovian delay conditioning task reflect reward-predictive signals

Pupils can signify various internal processes and states, such as attention, arousal, and working memory. Changes in pupil size have been associated with learning speed, prediction of future events, and deviations from the prediction in human studies. However, the detailed relationships between pupil size changes and prediction are unclear. We explored pupil size dynamics in mice performing a Pavlovian delay conditioning task. A head-fixed experimental setup combined with deep-learning-based image analysis enabled us to reduce spontaneous locomotor activity and to track the precise dynamics of pupil size of behaving mice. By setting up two experimental groups, one for which mice were able to predict reward in the Pavlovian delay conditioning task and the other for which mice were not, we demonstrated that the pupil size of mice is modulated by reward prediction and consumption, as well as body movements, but not by unpredicted reward delivery. Furthermore, we clarified that pupil size is still modulated by reward prediction even after the disruption of body movements by intraperitoneal injection of haloperidol, a dopamine D2 receptor antagonist. These results suggest that changes in pupil size reflect reward prediction signals. Thus, we provide important evidence to reconsider the neuronal circuit involved in computing reward prediction error. This integrative approach of behavioral analysis, image analysis, pupillometry, and pharmacological manipulation will pave the way for understanding the psychological and neurobiological mechanisms of reward prediction and the prediction errors essential to learning and behavior.

Synthesis and Evaluation of Poly(3-hydroxypropyl Ethylene-imine) and Its Blends with Chitosan Forming Novel Elastic Films for Delivery of Haloperidol

This study aimed to develop novel elastic films based on chitosan and poly(3-hydroxypropyl ethyleneimine) or P3HPEI for the rapid delivery of haloperidol. P3HPEI was synthesized using a nucleophilic substitution reaction of linear polyethyleneimine (L-PEI) with 3-bromo-1-propanol. ¹H-NMR and FTIR spectroscopies confirmed the successful conversion of L-PEI to P3HPEI, and the physicochemical properties and cytotoxicity of P3HPEI were investigated. P3HPEI had good solubility in water and was significantly less toxic than the parent L-PEI. It had a low glass transition temperature (T_g = -38.6 °C). Consequently, this new polymer was blended with chitosan to improve mechanical properties, and these materials were used for the rapid delivery of haloperidol. Films were prepared by casting from aqueous solutions and then evaporating the solvent. The miscibility of polymers, mechanical properties of blend films, and drug release profiles from these formulations were investigated. The blends of chitosan and P3HPEI were miscible in the solid state and the inclusion of P3HPEI improved the mechanical properties of the films, producing more elastic materials. A 35:65 (%w/w) blend of chitosan-P3HPEI provided the optimum glass transition temperature for transmucosal drug delivery and so was selected for further investigation with haloperidol, which was chosen as a model hydrophobic drug. Microscopic and X-ray diffractogram (XRD) data indicated that the solubility of the drug in the films was ~1.5%. The inclusion of the hydrophilic polymer P3HPEI allowed rapid drug release within ~30 min, after which films disintegrated, demonstrating that the formulations are suitable for application to mucosal surfaces, such as in buccal drug delivery. Higher release with increasing drug loading allows flexible dosing. Blending P3HPEI with chitosan thus allows the selection of desirable physicochemical and mechanical properties of the films for delivery of haloperidol as a poorly water-soluble drug.

The effects of cannabidiol on behavioural and oxidative stress parameters induced by prolonged haloperidol administration

OBJECTIVES

We investigated the influence of oral cannabidiol (CBD) on vacuous chewing movements (VCM) and oxidative stress parameters induced by short- and long-term administration of haloperidol in a rat model of tardive dyskinesia (TD).

METHODS

Haloperidol was administered either sub-chronically via the intraperitoneal (IP) route or chronically via the intramuscular (IM) route to six experimental groups only or in combination with CBD. VCM and oxidative stress parameters were assessed at different time points after the last dose of medication.

RESULTS

Oral CBD (5 mg/kg) attenuated the VCM produced by sub-chronic administration of haloperidol (5 mg/kg) but had minimal effects on the VCM produced by chronic administration of haloperidol (50 mg/kg). In both sub-chronic and chronic haloperidol groups, there were significant changes in brain antioxidant parameters compared with CBD only and the control groups. The sub-chronic haloperidol-only group had lower glutathione activity compared with sub-chronic haloperidol before CBD and the control groups; also, superoxide dismutase, catalase, and 2,2-diphenyl-1-picrylhydrazyl activities were increased in the sub-chronic (IP) haloperidol only group compared with the CBD only and control groups. Nitric oxide activity was increased in sub-chronic haloperidol-only group compared to the other groups; however, the chronic haloperidol group had increased malondialdehyde activity compared to the other groups.

CONCLUSIONS

Our findings indicate that CBD ameliorated VCM in the sub-chronic haloperidol group before CBD, but marginally in the chronic haloperidol group before CBD. There was increased antioxidant activity in the sub-chronic group compared to the chronic group.

Beneficial effects of atypical antipsychotics on object recognition deficits after adolescent toluene exposure in mice: involvement of 5-HT1A receptors

Background: Inhalant (e.g. toluene) misuse by adolescents has been linked to psychosis and persistent cognitive deficits. Identifying effective strategies to improve cognitive deficits following chronic toluene misuse is critical. 5-HT_1A receptor has been proposed as a target for the treatment of cognitive deficits.Objectives: We compared the effects of antipsychotics on recognition deficits after adolescent toluene exposure in mice and elucidated the role of 5-HT_1A receptors in the cognition-improving effects of antipsychotics.Methods: Male NMRI mice (n = 279) received one injection per day of either toluene (750 mg/kg) or corn oil at postnatal days 35-39 and 42-46. Thereafter, the acute and subchronic effects of haloperidol, aripiprazole, or clozapine on toluene-induced recognition deficits were evaluated by novel object recognition test.Results: Acute administration of aripiprazole (p < .05) and clozapine (p < .01), but not haloperidol, significantly attenuated the toluene-induced recognition deficits. Pretreatment with 5-HT_1A receptor antagonist WAY -100,635 (p < .05) blocked their beneficial effects. Moreover, 5-HT_1A receptor agonist buspirone (p < .01) ameliorated the toluene-induced recognition deficits, which was reversed by WAY -100,635 (p < .001). Finally, after repeated treatment with clozapine, aripiprazole, and buspirone daily for 14 days, the impaired object recognition in toluene-exposed mice was significantly improved (p < .05) and the beneficial effects lasted for at least 2 weeks (p < .05).Conclusions: The results indicate that clozapine and aripiprazole, which display 5-HT_1A agonist properties, restored cognitive deficits in mice induced by adolescent toluene exposure. These findings suggest that these antipsychotics should be further explored as a potential treatment option for cognitive deficits in patients with psychosis associated with toluene exposure.

Association of Polymorphism with the Steady-State Concentration of Haloperidol in Patients with Alcohol-Induced Psychotic Disorders

Background

CYP2D6 subfamily isoenzymes play an important role in the biotransformation of haloperidol, and their activity may influence the efficacy and safety of haloperidol. The use of haloperidol is often associated with the occurrence of adverse drug reactions (ADRs), such as dyskinesia, acute dystonia, and orthostatic hypotension. Previous studies have demonstrated the relationship between the CYP2D6*4 genetic polymorphism and CYP2D6 activity, as well as haloperidol efficacy and safety rates.

Purpose

To evaluate the association of CYP2D6*4 genetic polymorphism with the steady-state concentration of haloperidol in patients with acute alcohol-induced psychotic disorders (AIPDs).

Material and methods

The study involved 100 male patients with AIPD (average age 41.4 ± 14.4 years) who received haloperidol by injections in a dose of 5-10 mg/day. The efficacy profile was assessed using a validated psychometric PANSS scale (Positive and Negative Syndrome Scale). Therapy safety was assessed using the internationally validated UKU (Side-Effect Rating Scale) and SAS (Simpson-Angus Scale for Extrapyramidal Symptoms) scales. Genotyping was performed with the real-time polymerase chain reaction.

Results

We revealed the statistically significant results in terms of therapy safety evaluation (dynamics of the UKU scores: (GG) 8.00 [7.00; 10.00], (GA) 15.0 [9.25; 18.0], p < 0.001; dynamics of the SAS scores: (GG) 11.0 [9.0; 14.0], (GA) 14.50 [12.0; 18.0], p < 0.001. Pharmacokinetic study showed a statistically significant difference across the groups with different genotypes: (GG) 3.13 [2.32; 3.95], (GA) 3.89 [2.92; 5.26], p = 0.010.

Conclusion

It can be concluded that patients with the GA genotype have a higher risk of ADRs compared to patients who carry the GG genotype. It was shown that CYP2D6*4 genetic polymorphism has a statistically significant effect on the steady-state concentration of haloperidol.

Herniarin, Dimethylfraxetin and Extracts from Tagetes lucida, in Psychosis Secondary to Ketamine and Its Interaction with Haloperidol

Tagetes lucida Cav., is a medicinal plant used in Mexico to alleviate different disorders related to alterations of the central nervous system, such as behaviors associated with psychosis. The present work evaluated the effect of different extracts separated from this plant, TlHex, TlEA, TlMet, and TlAq, and of two isolated coumarins, herniarin (HN) and dimethylfraxetin (DF), on haloperidol-induced catalepsy (HAL), and psychotic behaviors provoked with a glutamatergic antagonist, ketamine (KET) on ICR mice. The extracts TlEA, TlAq, and the isolated compounds HN and DF, induced an increment of the cataleptic effect of HAL. Schizophrenia-like symptoms caused by KET were analyzed through the behavior of the animals in the open field (OFT), forced swimming (FST), passive avoidance test (PAT), and social interaction test (SIT). Treatments derived from T. lucida could interact with this substance in all tests except for FST, in which only TlMet blocks its activity. Mainly, TlEA, TlAq, HN, and DF, blocked the effects of KET on stereotyped behavior, hyperlocomotion, cognitive impairment, and detriment in the social interaction of rodents. T. lucida interacted with dopaminergic and glutamatergic systems.

Haloperidol-Induced Immediate Early Genes in Striatopallidal Neurons Requires the Converging Action of cAMP/PKA/DARPP-32 and mTOR Pathways

Antipsychotics share the common pharmacological feature of antagonizing the dopamine 2 receptor (D2R), which is abundant in the striatum and involved in both the therapeutic and side effects of this drug’s class. The pharmacological blockade of striatal D2R, by disinhibiting the D2R-containing medium-sized spiny neurons (MSNs), leads to a plethora of molecular, cellular and behavioral adaptations, which are central in the action of antipsychotics. Here, we focused on the cell type-specific (D2R-MSNs) regulation of some striatal immediate early genes (IEGs), such as cFos, Arc and Zif268. Taking advantage of transgenic mouse models, pharmacological approaches and immunofluorescence analyses, we found that haloperidol-induced IEGs in the striatum required the synergistic activation of A2a (adenosine) and NMDA (glutamate) receptors. At the intracellular signaling level, we found that the PKA/DARPP-32 and mTOR pathways synergistically cooperate to control the induction of IEGs by haloperidol. By confirming and further expanding previous observations, our results provide novel insights into the regulatory mechanisms underlying the molecular/cellular action of antipsychotics in the striatum.

Antipsychotic drugs induce vascular defects in hematopoietic organs

Antipsychotic agents are clinically utilized to treat schizophrenia and other mental disorders. These drugs induce neurological and metabolic side effects, but their influence on blood vessels remains largely unknown. Here, we show that haloperidol, one of the most frequently prescribed antipsychotic agents, induces vascular defects in bone marrow. Acute haloperidol treatment results in vascular dilation that is specific to hematopoietic organs. This vessel dilation is associated with disruption of hematopoiesis and hematopoietic stem/progenitor cells (HSPCs), both of which are reversible after haloperidol withdrawal. Mechanistically, haloperidol treatment blocked the secretion of vascular endothelial growth factor A (VEGF-A) from HSPCs. Genetic blockade of VEGF-A secretion from hematopoietic cells or inhibition of VEGFR2 in endothelial cells result in similar vessel dilation in bone marrow during regeneration after irradiation and transplantation. Conversely, VEGF-A gain of function rescues the bone marrow vascular defects induced by haloperidol treatment and irradiation. Our work reveals an unknown effect of antipsychotic agents on the vasculature and hematopoiesis with potential implications for drug application in clinic.

Haloperidol Versus Atypical Antipsychotics for Treating Delirium in Intensive Care Unit Patients: A Systematic Review

Delirium is a severe and variable neuropsychiatric illness that causes cognitive and behavioral problems as well as abrupt impairment in consciousness and focus. Due to the complex, dynamic, and multifaceted interactions between several risk factors, the etiology of delirium is unclear. Although its efficacy has not been thoroughly studied, haloperidol, a common antipsychotic medicine, is frequently used to prevent delirium in critically ill patients. When evaluating the atypical antipsychotic response rates for treating delirium, only a few trials have taken age into account.  Articles were searched for from PubMed, PubMed Central (PMC), and Science Direct, and reviewed systematically. A complete 225 articles were identified after applying the search strategy to these databases. Out of these, 12 were finalized for review. We reviewed the efficacy and safety of haloperidol with atypical antipsychotics for treating delirium in intensive care unit patients.

Haloperidol Prevents Oxytosis/Ferroptosis by Targeting Lysosomal Ferrous Ions in a Manner Independent of Dopamine D2 and Sigma-1 Receptors

Haloperidol is a widely used antipsychotic agent that exerts antipsychotic effects through a strong antagonism of dopamine D2 receptors. In addition, haloperidol is classified as a sigma-1 receptor (S1R) antagonist that prevents endogenous oxidative stress in cultured cells. However, pharmacological activities of haloperidol against oxidative stress remain unclear. Oxytosis/ferroptosis are iron-dependent nonapoptotic oxidative cell deaths that are regarded as two names for the same cell death pathway and the potential physiological relevance of oxytosis/ferroptosis in multiple diseases is suggested. In the present study, the effects of haloperidol on oxytosis/ferroptosis were investigated in S1R-knockdown mouse hippocampal HT22 cells. The results indicate that haloperidol is a strong inhibitor of oxytosis/ferroptosis independent of S1R. Imaging of HT22 cells with a newly developed fluorescent probe showed that haloperidol was localized to late endosomes and lysosomes and reduced the accumulation of lysosomal ferrous ions, resulting in reduced production of intracellular reactive oxygen species and inhibition of cell death. These results indicate that haloperidol is useful not only as an antipsychotic agent but also as a neuroprotective agent against endogenous oxidative stress via distinct mechanisms. Furthermore, lysosome-targeting ferroptosis inhibitors could be useful for the treatment of various diseases, including cancers, ischemia-reperfusion injury, and neurodegenerative disorders, which have been associated with ferroptosis.