Efficacy and safety of low-dose amisulpride versus olanzapine-fluoxetine combination in post-schizophrenic depression: A randomized controlled trial

Post-schizophrenic depression (PSD) increases the morbidity, mortality, and health burden in patients with schizophrenia. However, treatment of PSD is challenging due to the lack of substantial evidence of standard clinical practice. This study was aimed at comparing the efficacy and safety of low-dose amisulpride versus olanzapine-fluoxetine combination (OFC) in PSD. This was a randomized controlled trial conducted in sixty patients with PSD fulfilling the eligibility criteria. Recruited patients were randomized to receive either amisulpride at low dose (i.e., 100-300 mg/day) or OFC (5/10 mg + 20 mg) for eight weeks. The Calgary Depression Scale for Schizophrenia (CDSS), the Clinical Global Impression-Severity (CGI-S) and serum BDNF levels were assessed at baseline and after eight weeks of treatment. The change in the CDSS scores from baseline over eight weeks was significant in both the amisulpride and OFC groups. However, the changes were not significant when compared between the groups. Similarly, the changes in CGI-S scores and serum BDNF levels were significant in each group; but non-significant between the groups. A significant negative correlation was found between the changes in the CDSS scores and the serum BDNF levels in each group. No significant adverse events were noted in either group. Thus, to conclude, low-dose amisulpride can be a potential monotherapy in PSD with a favourable clinical outcome and safety profile (ClinicalTrials.gov ID: NCT04876521).

Role of prolactin in the protective effect of amisulpride against 1,2-Diacetylbenzene's neurotoxicity

Exposure to organic solvents is associated with various health problems, including neurodegenerative diseases. Among these solvents, 1,2-diethylbenzene is notable for its ability to produce a toxic metabolite, 1,2-Diacetylbenzene (DAB), which can cause memory impairment. Prolactin (PRL) is theorized to protect the central nervous system. Certain antipsychotic drugs, known for increasing PRL secretion, have shown to improve cognitive performance in psychotic Alzheimer's patients. Among these, amisulpride stands out for its high efficacy, limited side effects, and high selectivity for dopamine D2 receptors. In our study, we explored the potential of amisulpride to inhibit DAB-induced neurotoxicity via PRL activation. Our results show that amisulpride enhances the PRL/JAK/STAT, PI3K/AKT, and BDNF/ERK/CREB pathways, playing critical roles in PRL's neuroprotection pathways and memory formation. Additionally, amisulpride inhibited DAB-triggered NLRP3 inflammasome activation and apoptosis. Collectively, these findings suggest that amisulpride may be a promising therapeutic intervention for DAB-induced neurotoxicity, partly through activating the PRL pathway.

A Postoperative Nausea and Vomiting Update: Current information on New Drugs, Old Drugs, Rescue/Treatment, Combination Therapies and Nontraditional Modalities

This article's objective is to present the latest evidence and information on the management of postoperative nausea and vomiting (PONV). PONV continues to affect 30% of the surgical population causing patient dissatisfaction, extending length of stay, and increasing overall costs. This review includes the introduction of 2 new intravenous formulations of antiemetics (amisulpride, aprepitant), updates on nontraditional therapies, suggestions for combination prophylaxis, emerging data on rescue treatment, and considerations for special populations and settings. Both of the new antiemetics provide promising options for pharmacologic interventions for PONV with favorable safety profiles.

Effects of a single dose of amisulpride on functional brain changes during reward- and motivation-related processing using task-based fMRI in healthy subjects and patients with major depressive disorder - study protocol for a randomized clinical trial

BACKGROUND

Anhedonia and other deficits in reward- and motivation-related processing in psychiatric patients, including patients with major depressive disorder (MDD), represent a high unmet medical need. Neurobiologically, these deficits in MDD patients are mainly associated with low dopamine function in a frontostriatal network. In this study, alterations in brain activation changes during reward processing and at rest in MDD patients compared with healthy subjects are explored and the effects of a single low dose of the dopamine D2 receptor antagonist amisulpride are investigated.

METHODS

This is a randomized, controlled, double-blind, single-dose, single-center parallel-group clinical trial to assess the effects of a single dose of amisulpride (100 mg) on blood-oxygenation-level-dependent (BOLD) responses during reward- and motivation-related processing in healthy subjects (n = 60) and MDD patients (n = 60). Using functional magnetic resonance imaging (fMRI), BOLD responses are assessed during the monetary incentive delay (MID) task (primary outcome). Exploratory outcomes include BOLD responses and behavioral measures during the MID task, instrumental learning task, effort-based decision-making task, social incentive delay task, and probabilistic reward task as well as changes in resting state functional connectivity and cerebral blood flow.

DISCUSSION

This study broadly covers all aspects of reward- and motivation-related processing as categorized by the National Institute of Mental Health Research Domain Criteria and is thereby an important step towards precision psychiatry. Results regarding the immediate effects of a dopaminergic drug on deficits in reward- and motivation-related processing not only have the potential to significantly broaden our understanding of underlying neurobiological processes but might eventually also pave the way for new treatment options.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05347199. April 12, 2022.

Amisulpride attenuates 5-fluorouracil-induced cognitive deficits via modulating hippocampal Wnt/GSK-3β/β-catenin signaling in Wistar rats

Chemotherapy-induced cognitive impairment (CICI) is a general term describing cognitive dysfunction during/after treatment with chemotherapeutic agents. CICI represents a significant medical problem due to its increasing prevalence with the lack of robust therapeutic approaches. This study aimed at investigating the effects of chronic treatment with amisulpride (5 mg/kg/day) in the management of 5-fluorouracil (5-FU)-induced cognitive deficits in Wistar rats. Rats received 5 intraperitoneal injections of 5-FU (25 mg/kg every 3 days). 5-FU treatment induced impairments in spatial learning (reduction in object location discrimination ratio) and non-spatial learning (reduction in novel object recognition discrimination ratio). Moreover, 5-FU induced a decrease in the activity of the Wnt/GSK-3β/β-catenin pathway with a decrease in brain-derived neurotrophic factor (BDNF) level in the hippocampus. These changes were associated with an increase in the expression of the pro-inflammatory cytokines; tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), in hippocampal tissue sections accompanied by a decrease in the number of Ki-67 positive cells (indicating a decrease in proliferative capacity), a decrease in the Nissl's granules optical density (denoting neurodegeneration), a decrease in the number of viable intact neurons with an increase in the expression of β-amyloid and caspase-3. Amisulpride enhanced Wnt/GSK-3β/β-catenin signaling, increased BDNF levels, and abrogated 5-FU-induced neuroinflammation, apoptosis, β-amyloid accumulation, and neurodegenerative changes with an improvement of cognitive performance. This study draws attention to the pro-cognitive effects of amisulpride in 5-FU-exposed rats that could be attributed to enhancing hippocampal Wnt/GSK-3β/β-catenin signaling pathway, and this could offer a promising therapeutic option for subjects with CICI.

Facial mimicry is not modulated by dopamine D2/3 and opioid receptor antagonism

RATIONALE

According to theories of embodied cognition, facial mimicry - the spontaneous, low-intensity imitation of a perceived emotional facial expression - is first an automatic motor response, whose accompanying proprioceptive feedback contributes to emotion recognition. Alternative theoretical accounts, however, view facial mimicry as an emotional response to a rewarding stimulus, and/or an affiliative signal, and thus reject the view of an automatic motor copy.

OBJECTIVES

To contribute to this debate and further investigate the neural basis of facial mimicry, as well as its relation to reward processing, we measured facial reactions to dynamic happy and angry faces after pharmacologically manipulating the opioid and dopamine systems - respectively, thought to subserve 'liking' and 'wanting' of rewards.

METHODS

In a placebo-controlled, double-blind experiment, 130 volunteers received in a between-subjects design 50 mg of the opioidergic antagonist naltrexone, 400 mg of the dopaminergic antagonist amisulpride, or placebo.

RESULTS

Clear occurrence of facial mimicry, measured 4 h after drug intake with electromyography (EMG) of the zygomaticus major and corrugator supercilii muscles, was found. However, facial mimicry was not affected by either compound, as shown with both frequentist statistics, and a Bayesian asymptotic regression model.

CONCLUSIONS

This null finding does not support the hypothesis that facial mimicry (of happiness) reflects an emotional response to a rewarding stimulus, leaving open the possibility of facial mimicry being an automatic motor copy. The results are relevant to the discussion about the psychological nature and the neural basis of facial mimicry, although they should be considered preliminary, given the challenges of interpreting null findings when targeting a novel effect of unknown size.

Population pharmacokinetics of Amisulpride in Chinese patients with schizophrenia with external validation: the impact of renal function

Introduction: Amisulpride is primarily eliminated via the kidneys. Given the clear influence of renal clearance on plasma concentration, we aimed to explicitly examine the impact of renal function on amisulpride pharmacokinetics (PK) via population PK modelling and Monte Carlo simulations. Method: Plasma concentrations from 921 patients (776 in development and 145 in validation) were utilized. Results: Amisulpride PK could be described by a one-compartment model with linear elimination where estimated glomerular filtration rate, eGFR, had a significant influence on clearance. All PK parameters (estimate, RSE%) were precisely estimated: apparent volume of distribution (645 L, 18%), apparent clearance (60.5 L/h, 2%), absorption rate constant (0.106 h-1, 12%) and coefficient of renal function on clearance (0.817, 10%). No other significant covariate was found. The predictive performance of the model was externally validated. Covariate analysis showed an inverse relationship between eGFR and exposure, where subjects with eGFR= 30 mL/min/1.73 m2 had more than 2-fold increase in AUC, trough and peak concentration. Simulation results further illustrated that, given a dose of 800 mg, plasma concentrations of all patients with renal impairment would exceed 640 ng/mL. Discussion: Our work demonstrated the importance of renal function in amisulpride dose adjustment and provided a quantitative framework to guide individualized dosing for Chinese patients with schizophrenia.

A 5-year retrospective study of amisulpride steady-state plasma concentration in patients with schizophrenia in real-life settings based on therapeutic drug monitoring data

OBJECTIVE

Here, we present a retrospective analysis of the last 5 years' data collected in real-life settings as direct evidence to evaluate the optimal therapeutic window of amisulpride (AMI) for psychiatric patients.

METHODS

Retrospective analysis of the therapeutic drug monitoring (TDM) results of AMI in outpatients and inpatients were obtained from the Xi'an Mental Health Center from 2017 to 2021.

RESULTS

The interquartile (P25-P75) AMI concentrations ranged 212.20-574.25 ng/mL. The results showed that the proportion of outpatients who received TDM once was significantly higher than that of inpatients who received TDM once (P < 0.001), whereas the reverse was true for those who experienced TDM more than twice (P < 0.001). Higher estimated plasma concentrations were identified in inpatients, female patients, and patients over 59 years of age. Nearly 57.21% of the samples had high concentrations (>320 ng/mL).

CONCLUSIONS

The optimal therapeutic reference range for AMI may require reconstruction to guide the use of AMI for the treatment of schizophrenia.

Repetitive transcranial magnetic stimulation combined with olanzapine and amisulpride for treatment-refractory schizophrenia

BACKGROUND

Treatment-refractory schizophrenia (TRS), accounting for approximately 30% of all schizophrenia cases, has poor treatment response and prognosis despite treatment with antipsychotic drugs.

AIM

To analyze the therapeutic effectiveness of repetitive transcranial magnetic stimulation (rTMS) combined with olanzapine (OLZ) and amisulpride (AMI) for TRS and its influence on the patient’s cognitive function.

METHODS

This study enrolled 114 TRS patients who received treatment at the First Affiliated Hospital of Zhengzhou University between July 2019 and July 2022. In addition to the basic OLZ + AMI therapy, 54 cases of the control group (Con group) received modified electroconvulsive therapy, while 60 cases of the research group (Res group) received rTMS. Data on therapeutic effectiveness, safety (incidence of drowsiness, headache, nausea, vomiting, or memory impairment), Positive and Negative Symptom Scale, Montreal Cognitive Assessment Scale, and Schizophrenia Quality of Life Scale were collected from both cohorts for comparative analyses.

RESULTS

The Res group elicited a higher overall response rate and better safety profile when compared with the Con group. Additionally, a significant reduction was observed in the post-treatment Positive and Negative Symptom Scale and Schizophrenia Quality of Life Scale scores of the Res group, presenting lower scores than those of the Con group. Furthermore, a significant increase in the Montreal Cognitive Assessment Scale score was reported in the Res group, with higher scores than those of the Con group.

CONCLUSION

The treatment of TRS with rTMS and OLZ + AMI is effective and safe. Moreover, it can alleviate the patients’ mental symptoms, improve their cognitive function and quality of life, and has a high clinical application value.

Does drug use affect the efficacy of amisulpride, aripiprazole and olanzapine in patients with schizophrenia spectrum disorders? Results from a pragmatic, randomised study

OBJECTIVES

Drug use is prevalent in patients with schizophrenia spectrum disorders (SSD) but there is limited knowledge about the influence of drug use on the effectiveness of antipsychotic medication. This secondary explorative study compared the effectiveness of three antipsychotics in patients with SSD, with and without drug use.

METHODS

The BeSt InTro multi-centre, head to head, rater-blinded randomised study compared amisulpride, aripiprazole and olanzapine over a 1-year follow-up period. All patients (n = 144) were aged ≥18 years and met the ICD-10 criteria for SSD (F20-29). Clinical symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). The primary outcome was reduction of a PANSS positive subscale score.

RESULTS

At baseline, 38% of all patients reported drug use in the last 6 months before inclusion, with cannabis as the main drug (85%), followed by amphetamine-type stimulants (45%), sedatives (26%), hallucinogens (19%), cocaine (13%), opiates (4%), GHB (4%), solvents (4%), analgesics (4%) and anabolic steroids (2%). The predominant pattern was the use of several drugs. There were no significant overall differences in the PANSS positive subscale score reduction for the three studied antipsychotics among patients either with or without drug use. In the drug use group, older patients treated with amisulpride showed a greater PANSS positive subscale score reduction during the treatment period compared to younger patients.

CONCLUSION

The current study showed that drug use does not appear to affect the overall effectiveness of amisulpride, aripiprazole and olanzapine in patients with SSD. However, amisulpride may be a particularly suitable choice for older patients with drug use.

Genetic association of the rs17782313 polymorphism with antipsychotic-induced weight gain

RATIONALE

Weight gain is a frequent side effect of treatment with SGAs (second-generation antipsychotics) and a leading cause for nonadherence. Several candidate genes have been identified that could influence the amount of AIWG (antipsychotic-induced weight gain). The polymorphism rs17782313 near the MC4R (human melanocortin 4 receptor gene) was strongly associated with obesity in a large scale GWAS (genome wide association study), yet previous studies investigating its impact on AIWG did not lead to a definite conclusion regarding its effect. In particular, they were all relatively short and had a naturalistic design.

OBJECTIVE

We therefore examined the influence of the rs17782313 polymorphism on SGA-related weight gain.

METHODS

Participants of a multicenter randomized, controlled, double-blind study comparing two treatment strategies in individuals with schizophrenia or schizoaffective disorder were genotyped using a rapid-cycle polymerase chain reaction. Up to 252 individuals completed the first 2 weeks (phase I), 212 the entire 8 weeks (hence 'completers'). Patients received either amisulpride or olanzapine or both consecutively. Thirty-seven had their first episode. Weight gain occurring in different genotypes was statistically compared and confounding factors were adjusted by stepwise multiple linear regression. A correction for multiple testing was included.

RESULTS

Within 212 'completers', carriers of the C allele had a higher absolute weight gain than those homozygous for the T allele (2.6 kg vs. 1.2 kg), though this observation was not significant (P = 0.063). In the amisulpride subpopulation, this association appeared stronger and reached significance (2.5 kg vs. 0.7 kg, P = 0.043), though failed to remain significant after correction for multiple testing. A stepwise multiple linear regression showed a significant association in both the whole study population (P < 0.001) and the amisulpride subpopulation (P < 0.001).

CONCLUSION

Our results indicate that the rs17782313 polymorphism might influence antipsychotic-induced weight gain and therefore confirm some of the earlier conclusions.

NiFe-based Prussian blue analogue nanopolygons hybridized with functionalized glyoxal polymer as a voltammetric platform for the determination of amisulpride in biological samples

A novel voltammetric platform based on pencil graphite electrode (PGE) modification has been proposed, containing bimetallic (NiFe) Prussian blue analogue nanopolygons decorated with electro-polymerized glyoxal polymer nanocomposites (p-DPG NCs@NiFe PBA Ns/PGE). Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square wave voltammetry (SWV) were utilized to investigate the electrochemical performance of the proposed sensor. The analytical response of p-DPG NCs@NiFe PBA Ns/PGE was evaluated through the quantity of amisulpride (AMS), one of the most common antipsychotic drugs. Under the optimized experimental and instrumental conditions, the method showed linearity over the range from 0.5 to 15 × 10-8 mol L-1 with a good correlation coefficient (R = 0.9995) and a low detection limit (LOD) reached, 1.5 nmol L-1, with excellent relative standard deviation for human plasma and urine samples. The interference effect of some potentially interfering substances was negligible, and the sensing platform demonstrated an outstanding reproducibility, stability, and reusability. As a first trial, the proposed electrode aimed to shed light on the AMS oxidation mechanism, where the oxidation mechanism was monitored and elucidated using the FTIR technique. It was also found that the prepared p-DPG NCs@NiFe PBA Ns/PGE platform had promising applications for the simultaneous determination of AMS in the presence of some co-administered COVID-19 drugs, which could be attributed to the large active surface area, and high conductivity of bimetallic nanopolygons.

Sonic hedgehog pathway as a new target of atypical antipsychotics: Revisiting of amisulpride and aripiprazole effects in a rat model of schizophrenia

OBJECTIVES

Schizophrenia is a chronic mental illness presented by cognitive deficits that precede its positive and negative symptoms. Sonic hedgehog (Shh)-pathway contributes to its pathophysiology. Shh has a role in neurogenesis as it regulates proliferation and survival of neural cells. In this study, effects of the anti-psychotics Amisulpride and/or Aripiprazole on the Shh-pathway and its relation to cognitive functions and neurogenesis in a rat model of schizophrenia were tested.

METHODS

60 male Wistar rats were allocated into the following groups: control, socially isolated, amisulpride and/or aripiprazole-treated groups. Rats were then subjected to behavioral, biochemical, and histopathological tests to assess the impact of these drugs on Shh-pathway.

KEY FINDINGS

Cognitive-dysfunction was evidenced in socially isolated group in novel object, three-chamber, and Morris water maze tests, associated by disorganised Shh-pathway proteins levels concentrations, increased glial fibrillary acidic protein (GFAP)-stained astrocytes. Treated groups favorably reversed these changes evidenced by increased Shh, transmembrane patched-1 and smoothened, glioma-associated-oncogene (GLI)-1 levels, dopamine-1 receptors and brain derived neurotrophic factor, and decreased GLI-3 protein, GFAP immune reaction in astrocytes and inflammatory markers compared to socially isolated group.

CONCLUSION

Amisulpride and/or aripiprazole have a favorable role in turning on Shh-pathway with subsequent beneficial cognitive and neurogenesis effects.

Does partial blockade of dopamine D2 receptors with Amisulpride cause anhedonia? An experimental study in healthy volunteers

BACKGROUND

Anhedonia is a frequent cause of functional im^pairment in psychosis. Although it is plausible that medication-induced D2 receptor blockade could diminish hedonic responding, there is little experimental research testing this hypothesis in humans.

METHODS

To inspect possible effects of partial D2 blockade on hedonic experiences, we administered 300 mg of Amisulpride or placebo to 85 participants in a randomized, double-blind, placebo-controlled trial. Participants were then subjected to an emotional evocation task utilizing standardized pictorial pleasant, neutral, and unpleasant stimuli.

RESULTS

We observed lower positivity ratings in the Amisulpride group compared to placebo across all stimulus categories (p = .026, f = 0.25) and no group differences in negativity or arousal ratings. The Amisulpride group also showed lower electrodermal responses across all stimulus categories compared to placebo (p = .017, f = 0.27). The electrodermal response was especially diminished for pleasant stimuli.

CONCLUSION

We interpret our findings as evidence that D2 blockade via Amisulpride can reduce at-the-moment hedonic responsivity in healthy volunteers. If these results can be confirmed in drug-naïve clinical samples, this would indicate that antipsychotic medication contributes to clinical anhedonia, probably via antagonistic effects at the dopamine D2 receptor.

Amisulpride augmentation therapy improves cognitive performance and psychopathology in clozapine-resistant treatment-refractory schizophrenia: a 12-week randomized, double-blind, placebo-controlled trial

BACKGROUND

Although clozapine is an effective option for treatment-resistant schizophrenia (TRS), there are still 1/3 to 1/2 of TRS patients who do not respond to clozapine. The main purpose of this randomized, double-blind, placebo-controlled trial was to explore the amisulpride augmentation efficacy on the psychopathological symptoms and cognitive function of clozapine-resistant treatment-refractory schizophrenia (CTRS) patients.

METHODS

A total of 80 patients were recruited and randomly assigned to receive initial clozapine plus amisulpride (amisulpride group) or clozapine plus placebo (placebo group). Positive and Negative Syndrome Scale (PANSS), Scale for the Assessment of Negative Symptoms (SANS), Clinical Global Impression (CGI) scale scores, Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), Treatment Emergent Symptom Scale (TESS), laboratory measurements, and electrocardiograms (ECG) were performed at baseline, at week 6, and week 12.

RESULTS

Compared with the placebo group, amisulpride group had a lower PANSS total score, positive subscore, and general psychopathology subscore at week 6 and week 12 (P_Bonferroni < 0.01). Furthermore, compared with the placebo group, the amisulpride group showed an improved RBANS language score at week 12 (P_Bonferroni < 0.001). Amisulpride group had a higher treatment response rate (P = 0.04), lower scores of CGI severity and CGI efficacy at week 6 and week 12 than placebo group (P_Bonferroni < 0.05). There were no differences between the groups in body mass index (BMI), corrected QT (QTc) intervals, and laboratory measurements. This study demonstrates that amisulpride augmentation therapy can safely improve the psychiatric symptoms and cognitive performance of CTRS patients.

CONCLUSION

This study indicates that amisulpride augmentation therapy has important clinical significance for treating CTRS to improve clinical symptoms and cognitive function with tolerability and safety. Trial registration Clinicaltrials.gov identifier- NCT03652974. Registered August 31, 2018, https://clinicaltrials.gov/ct2/show/NCT03652974.

The overall assessment of simultaneous photocatalytic degradation of Cimetidine and Amisulpride by using chemical and genotoxicological approaches

Pharmaceutical Active Compounds (PhACs) are of particular interest among the emerging contaminants detected in the aquatic environment. Commonly, PhACs exist as complex mixtures in aquatic systems, causing potential adverse effects to the environment and human health than those of individual compounds. Based on the increasing interest in the contamination of water resources by PhACs, the photocatalytic degradation of Cimetidine and Amisulpride as a mixture in combination with their toxic and genotoxic effects before and after the treatment were evaluated for the first time. The toxic, genotoxic and cytotoxic effects were investigated using the Trypan Blue Exclusion Test and the Cytokinesis Block MicroNucleus (CBMN) assay in cultured human lymphocytes. The photocatalytic degradation of the PhACs was studied in ultrapure water and environmentally relevant matrices using UV-A and visible (Vis) irradiation and C-TiO₂ (TiO₂ Kronos vlp 7000) as photocatalyst. High removal percentages were observed for both compounds under UV-A and Vis irradiation in ultrapure water. In lake and drinking water a slower degradation rate was shown that could be attributed to the complex composition of these matrices. Scavenging experiments highlighted the significant role of h⁺ and O₂^●- in the degradation mechanisms under both irradiation sources. Oxidation, dealkylation and deamination were the main degradation pathways. Regarding the individual compounds, Amisulpride was found to be more cytotoxic than Cimetidine. No significant differences of the genotoxic effects during the treatment were observed. However, a slight increase in cytotoxicity was observed at the first stages of the process. At the end of the process under both UV-A and Vis light, non-significant cytotoxic/toxic effects were observed. Based on the results, heterogeneous photocatalysis can be considered as an effective process for the treatment of complex mixtures without the formation of harmful transformation products.

Amisulpride withdrawal akathisia responding to aripiprazole with propranolol in first-onset psychosis: a case report

BACKGROUND

Akathisia tends to develop as an early complication of antipsychotic treatment in a dose-dependent manner. Although withdrawal akathisia has been reported after the discontinuation or dose reduction of typical antipsychotic drugs, akathisia following atypical antipsychotic drug withdrawal remains a rare phenomenon.

CASE PRESENTATION

A 24-year-old woman with an acute psychotic episode was admitted and initially treated with aripiprazole. The aripiprazole dose was titrated up to 30 mg/day over 9 days and maintained for the next 3 days; however, her psychotic symptoms persisted without change. She was switched to amisulpride, with the dose increased over 2 weeks to 1000 mg/day. Subsequently, although the patient's psychotic episode subsided, her serum prolactin levels increased markedly. After discharge, the amisulpride dose was increased to 1200 mg/day owing to auditory hallucinations and was maintained with quetiapine (100-200 mg/day) and benztropine (1 mg/day) for 13 weeks. Given the potential for hyperprolactinemia as a side effect, the amisulpride dose was reduced to 800 mg/day concurrently with the discontinuation of benztropine; however, these changes resulted in severe restlessness without other extrapyramidal symptoms. The withdrawal akathisia disappeared over 2 weeks after switching to aripiprazole (10 mg/day) with propranolol (40 mg/day) and the patient's prolactin levels had normalized after 6 months of aripiprazole monotherapy.

CONCLUSIONS

The present case highlights the potential for the development of withdrawal akathisia when the dose of amisulpride is tapered abruptly. Thus, a slow tapering and careful monitoring are recommended when switching from amisulpride to other antipsychotic drugs. Furthermore, this case suggests that changing the regimen to aripiprazole with propranolol may be a potential option for amisulpride withdrawal akathisia superimposed on pre-existing hyperprolactinemia.

A Randomized, Double-blind, Placebo-controlled Proof-of-Concept Trial to Evaluate the Efficacy and Safety of Non-racemic Amisulpride (SEP-4199) for the Treatment of Bipolar I Depression

BACKGROUND

Non-racemic amisulpride (SEP-4199) is an 85:15 ratio of aramisulpride:esamisulpride with a 5-HT7 and D2 receptor binding profile optimized for the treatment of bipolar depression. The aim of this study was to evaluate the efficacy and safety of SEP-4199 for the treatment of bipolar depression.

METHODS

Patients meeting DSM-5 criteria for bipolar I depression were randomized to 6 weeks of double-blind, placebo-controlled treatment with SEP-4199 200 mg/d or 400 mg/d. The primary endpoint was change in the Montgomery-Asberg Depression Rating Scale (MADRS) at Week 6. The primary efficacy analysis population consisted of patients in Europe and US (n = 289); the secondary efficacy analysis population (ITT; n = 337) included patients in Japan.

RESULTS

Endpoint improvement in MADRS total score was observed on both the primary analysis for SEP-4199 200 mg/d (P = 0.054; effect size [ES], 0.31) and 400 mg/d (P = 0.054; ES, 0.29), and on the secondary (full ITT) analysis for SEP-4199 200 mg/d (P = 0.016; ES, 0.34) and 400 mg/d (P = 0.024; ES, 0.31). Study completion rates were 81% on SEP-4199 200 mg/d, 88% on 400 mg/d, and 86% on placebo. SEP-4199 had low rates of individual adverse events (<8%) and minimal effects on weight and lipids; median increases in prolactin were +83.6 μg/L on 200 mg/d, +95.2 μg/L on 400 mg/d compared with 0.0 μg/L on placebo.

LIMITATIONS

The study excluded patients with bipolar II depression and serious psychiatric or medical comorbidity.

CONCLUSION

Study results provide preliminary proof of concept, needing confirmation in subsequent randomized trials, for the efficacy of non-racemic amisulpride in bipolar depression.

Nose-to-brain delivery of amisulpride-loaded lipid-based poloxamer-gellan gum nanoemulgel: In vitro and in vivo pharmacological studies

Unfavorable side effects of available antipsychotics limit the use of conventional delivery systems, where limited exposure of the drugs to the systemic circulation could reduce the associated risks. The potential of intranasal delivery is gaining interest to treat brain disorders by delivering the drugs directly to the brain circumventing the tight junctions of the blood-brain barrier with limited systemic exposure of the entrapped therapeutic. Therefore, the present research was aimed to fabricate, optimize and investigate the therapeutic efficacy of amisulpride (AMS)-loaded intranasal in situ nanoemulgel (AMS-NG) in the treatment of schizophrenia. In this context, AMS nanoemulsion (AMS-NE) was prepared by employing aqueous-titration method and optimized using Box-Behnken statistical design. The optimized nanoemulsion was subjected to evaluation of globule size, transmittance, zeta potential, and mucoadhesive strength, which were found to be 92.15 nm, 99.57%, -18.22 mV, and 8.90 g, respectively. The AMS-NE was converted to AMS-NG using poloxamer 407 and gellan gum. Following pharmacokinetic evaluation in Wistar rats, the brain C_max for intranasal AMS-NG was found to be 1.48-folds and 3.39-folds higher when compared to intranasal AMS-NE and intravenous AMS-NE, respectively. Moreover, behavioral investigations of developed formulations were devoid of any extrapyramidal side effects in the experimental model. Finally, outcomes of the in vivo hematological study confirmed that intranasal administration of formulation for 28 days did not alter leukocytes and agranulocytes count. In conclusion, the promising results of the developed and optimized intranasal AMS-NG could provide a novel platform for the effective and safe delivery of AMS in schizophrenic patients.

Prediction of Self-Report Cognitive Function for the Symptomatic Remission in Schizophrenia Treated with Amisulpride: a Multicenter, 8-Week Case-Control Study

This study aimed to determine whether self-report cognitive function is a predictor of symptomatic remission in amisulpride-treated schizophrenia. Patients with DSM-IV schizophrenia diagnoses who received amisulpride treatment, were recruited. Each patient received amisulpride with a flexible-dose strategy of 400-800 mg daily for eight weeks. Remission was defined by a shorter version of the Positive and Negative Symptom Scale(PANSS)criteria, which includes six items (PANSS-6) with scores of less than three in each item(criteria A) or total six scores of less than fourteen(criteria B). Three hundred and three patients completed the study in 15 hospitals in China. By criteria A, 244 (80.5%) achieved symptomatic remission at endpoint, and 258 (85.1%) by criteria B. Duration of illness (DOI) (criteria A: t = 2.31, P = 0.025,criteria B:t = 2.24,p = 0.026) and perceived deficits questionnaire at baseline (PDQ20 Day0) (criteria A: t = 3.32, P = 0.001,criteria B:t = 2.76,p = 0.006) in remission groups were less than that in non-remission groups. Logistic regression analysis took into account sex, age, age-onset, DOI, and PDQ20(Day0), and showed that PDQ20(Day0) was a predictor for symptomatic remission in criteria A (B = - 0.02, P = 0.014) and criteria B (B = - 0.03, P = 0.005). The odds ratio (OR) of achieving remission will be reduced by 2% in criteria A and 3% in criteria B. There were no significant differences in gender composition, age, BMI, education level, age-onset, a daily dose of amisulpride and the percentage of PDQ20 Improvement between remission and nonremission in criteria A or criteria B. Receiver operating characteristic(ROC) curves were found for PDQ20(Day0) to define the precise scores to predict remission of schizophrenia (criteria A:AUC = 0.614, S.E. = 0.041, 95% CI = 0.535-0.694, p = 0.007; criteria B:AUC = 0.633, S.E. = 0.045, 95% CI = 0.545-0.721, p = 0.005). Our data suggest that an early self-report cognitive function in amisulpride-treated schizophrenia is important in predicting for symptomatic remission, the fewer scores of PDQ20 at baseline mean the patients have less daily cognitive difficulty, the more likely the patient is to achieve symptomatic remission.

Study on the relationship among dose, concentration and clinical response in Chinese schizophrenic patients treated with Amisulpride

OBJECTIVE

To provide therapeutic window of amisulpride dose and serum concentration.

METHODS

194 schizophrenics were assessed with PANSS. The concentration of Amisulpride in blood was tested. And relationship with concentration was analyzed.

RESULTS

The dose of amisulpride was 100mg∼1200 mg/d(555+/-218), plasma concentration was 20∼1280 ng/mL(349+/-223) and C/D ratio was 0.07∼1.65 (0.63+/-0.34). The correlation of dose and concentration was significantly correlated (r = 0.55; P < 0.05).It was found that concentration(P < 0.001), C/D ratio(r = 0.383, P < 0.001), rather than dose (-0.042,p > 0.05) related to age significantly.It was found no differences in dose(p > 0.05), concentration (p > 0.05) and C/D ratio(p > 0.05) between male and female patients. The change ratio of positive symptom was 10 %∼90 %, negative symptom was 5∼80 %, general symptoms was 5∼90 %, PANSS was 5∼90 %.The correlation between change ratio of positive symptom, general symptom and PANSS and dose, concentration were significant(P < 0.01), but not related with the change ratio of negative symptom(p>0.05).The both dose and concentration of amisulpride were higher significantly in effective group than that in ineffective group according to change ratio of positive symptom, negative symptom, general symptom and PANSS(P < 0.01).

CONCLUSION

The correlation of dose and concentration of amisulpride was significantly correlated. The recommended range 457∼637 ng/mL was suggested as average therapeutic window.

The effect of amisulpride, olanzapine, quetiapine, and aripiprazole single administration on c-Fos expression in vasopressinergic and oxytocinergic neurons of the rat hypothalamic paraventricular nucleus

Antipsychotics, including amisulpride (AMI), quetiapine (QUE), aripiprazole (ARI), and olanzapine (OLA), are used to treat mental illnesses associated with psychotic symptoms. The effect of these drugs on c-Fos expression in vasopressinergic (AVP) and oxytocinergic (OXY) neurons was studied in the hypothalamic paraventricular nucleus (PVN) of rats. The presence of c-Fos in AVP and OXY perikarya was investigated in seven PVN cells segregations: the anterior (Ant), dorsal cup (Dc), wing-shaped (Wi), periventricular zone (Pe), circle-shaped core (Co) and shell of core (Sh), and the posterior (pPVN) after an acute treatment with AMI-20 mg/kg, QUE-15 mg/kg, ARI-10 mg/kg, and OLA-5 mg/kg/bw in rats. Ninety min after treatments, the animals were sacrificed by transcardial perfusion with fixative and the PVN area sliced into 35 μm thick coronal sections for immunohistochemistry. The c-Fos was processed by avidin-biotin-peroxidase complex intensified with nickel-enhanced 3,3'-diaminobenzidine tetrahydrochloride. Visualization of AVP- and OXY-synthesizing neurons was achieved by a fluorescent marker Alexa Flour 568. The c-Fos-AVP and c-Fos-OXY colocalizations were evaluated from c-Fos stained sections merged with AVP or OXY ones. AMI, QUE, ARI, and OLA, single administration distinctly increased the c-Fos expression in each of the PVN cells segregations. QUE induced the highest magnitude of activation of AVP and OXY neurons, while OLA and AMI had only moderate effects. Incontestable variabilities detected in c-Fos expression in PVN AVP and OXY neurons extend the knowledge of selected antipsychotics extra-striatal actions and may also be helpful in a presumption of their possible functional impact.

Clinical Usefulness of Amisulpride Add-on Therapy in Schizophrenia Patients without Treatment Response to Second-generation Antipsychotics

Objective

The response to antipsychotics in patients with schizophrenia is still unsatisfactory. Therefore, augmentation with other antipsychotics is common in clinical situations. The purpose of this study was to evaluate the improvement of psychiatric symptoms and side effects after amisulpride add-on therapy.

Methods

Forty patients with schizophrenia or schizoaffective disorder without treatment response to second-generation antipsychotics were included in this study. Psychotic symptoms were evaluated using the Positive and Negative Syndrome Scale (PANSS) and the Korean version of Calgary Depression Scale for Schizophrenia (CDSS) at baseline, 4 weeks, and 8 weeks after the addition of amisulpride.

Results

Among the 29 subjects who completed the 8-week study, 34.5% were responders according to PANSS total score. At week 8, the mean positive (p < 0.001), negative (p < 0.001), general (p < 0.001), and total (p < 0.001) PANSS scores and CDSS scores (p = 0.002) showed significant improvement compared to baseline. There was no increase in extrapyramidal side effects according to Simpson Angus Scale (p = 0.379) and Barnes Akathisia Rating Scale (p = 0.070) and no weight gain (p = 0.308) after the add-on treatment.

Conclusion

The addition of amisulpride for schizophrenia patients without therapeutic response to second-generation antipsychotics is considered an effective and safe treatment. This study's results suggested that augmentation of second-generation antipsychotics with amisulpride could be a useful option for patients with schizophrenia unresponsive to second-generation antipsychotics. Further studies investigating the efficacy of amisulpride add-on therapy using placebo control are necessary to confirm these results.

No effect of a dopaminergic modulation fMRI task by amisulpride and L-DOPA on reward anticipation in healthy volunteers

RATIONALE

Dysregulation of dopaminergic neurotransmission, specifically altered reward processing assessed via the reward anticipation in the MID task, plays a central role in the etiopathogenesis of neuropsychiatric disorders.

OBJECTIVES

We hypothesized to find a difference in the activity level of the reward system (measured by the proxy reward anticipation) under drug administration versus placebo, in that amisulpride reduces, and L-DOPA enhances, its activity.

METHODS

We studied the influence of dopamine agonist L-DOPA and the antagonist amisulpride on the reward system using functional magnetic resonance imaging (fMRI) during a monetary incentive delay (MID) task in n = 45 healthy volunteers in a randomized, blinded, cross-over study.

RESULTS

The MID paradigm elicits strong activation in reward-dependent structures (such as ventral striatum, putamen, caudate, anterior insula) during reward anticipation. The placebo effect demonstrated the expected significant blood oxygen level-dependent activity in reward-dependent brain regions. Neither amisulpride nor L-DOPA led to significant changes in comparison with the placebo condition. This was true for whole-brain analysis as well as analysis of a pre-defined nucleus accumbens region-of-interest mask.

CONCLUSION

The present results cast doubt on the sensitivity of reward anticipation contrast in the MID task for assessing dopamine-specific changes in healthy volunteers by pharmaco-fMRI. While our task was not well-suited for detailed analysis of the outcome phase, we provide reasonable arguments that the lack of effect in the anticipation phase is not due to an inefficient task but points to unexpected behavior of the reward system during pharmacological challenge. Group differences of reward anticipation should therefore not be seen as simple representatives of dopaminergic states.

Cholinergic and dopaminergic effects on prediction error and uncertainty responses during sensory associative learning

Navigating the physical world requires learning probabilistic associations between sensory events and their change in time (volatility). Bayesian accounts of this learning process rest on hierarchical prediction errors (PEs) that are weighted by estimates of uncertainty (or its inverse, precision). In a previous fMRI study we found that low-level precision-weighted PEs about visual outcomes (that update beliefs about associations) activated the putative dopaminergic midbrain; by contrast, precision-weighted PEs about cue-outcome associations (that update beliefs about volatility) activated the cholinergic basal forebrain. These findings suggested selective dopaminergic and cholinergic influences on precision-weighted PEs at different hierarchical levels. Here, we tested this hypothesis, repeating our fMRI study under pharmacological manipulations in healthy participants. Specifically, we performed two pharmacological fMRI studies with a between-subject double-blind placebo-controlled design: study 1 used antagonists of dopaminergic (amisulpride) and muscarinic (biperiden) receptors, study 2 used enhancing drugs of dopaminergic (levodopa) and cholinergic (galantamine) modulation. Pooled across all pharmacological conditions of study 1 and study 2, respectively, we found that low-level precision-weighted PEs activated the midbrain and high-level precision-weighted PEs the basal forebrain as in our previous study. However, we found pharmacological effects on brain activity associated with these computational quantities only when splitting the precision-weighted PEs into their PE and precision components: in a brainstem region putatively containing cholinergic (pedunculopontine and laterodorsal tegmental) nuclei, biperiden (compared to placebo) enhanced low-level PE responses and attenuated high-level PE activity, while amisulpride reduced high-level PE responses. Additionally, in the putative dopaminergic midbrain, galantamine compared to placebo enhanced low-level PE responses (in a body-weight dependent manner) and amisulpride enhanced high-level precision activity. Task behaviour was not affected by any of the drugs. These results do not support our hypothesis of a clear-cut dichotomy between different hierarchical inference levels and neurotransmitter systems, but suggest a more complex interaction between these neuromodulatory systems and hierarchical Bayesian quantities. However, our present results may have been affected by confounds inherent to pharmacological fMRI. We discuss these confounds and outline improved experimental tests for the future.

The Opioid Interactions of the Antipsychotic Medications Risperidone and Amisulpride in Mice and Their Potential Use in the Treatment of Other Non-Psychotic Medical Conditions

Pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage. The opioid epidemic in the USA has highlighted the need for alternative treatments for pain. Following reports on the opioid interactions of various antipsychotic medications, we speculated that the involvement of the opioid system in some of the antipsychotics' mechanism of action may suggest their potential use in the treatment of pain. Risperidone is a neuroleptic with a potent dopamine D2 and serotonin 5-HT2 receptor-blocking activity as well as a high affinity for adrenergic and histamine H1 receptors. Amisulpride is a neuroleptic which selectively blocks dopamine D2 and D3 receptors. Both had a potent antinociceptive effect on ICR mice tested with a tail flick assay. That effect on both medications was antagonized by naloxone, indicating that at least some of the antinociceptive effects were mediated by an opioid mechanism of action. Further investigation found that β-Funaltrexamine hydrochloride (β-FNA), naloxonazine, and nor-Binaltorphimine dihydrochloride (nor-BNI) reversed the antinociceptive effect of both risperidone and amisulpride. Naltrindole at a dose that blocked [D-Pen2,D-Pen5]enkephalin (DPDPE, δ analgesia) blocked notably amisplride effect and only partially reversed that of risperidone. Risperidone induced an antinociceptive effect, implying involvement of μ and κ-opioid and δ-opioid mechanisms. Amisulpride-induced antinociception was mediated through selective involvement of all three opioid receptor subtypes. These findings emphasize the need for clinical trials to assess the possibility of extending the spectrum of medications available for the treatment of pain.

Hostility and aggressive behaviour in first episode psychosis: Results from the OPTiMiSE trial

AIM

The aim of this paper is to determine clinical factors related to hostility and disturbing and aggressive behaviour and to examine the effect of medication on these behaviours in FEP.

METHODS

Data from phase I and II of the OPTiMiSE trial are used. Outcome measures are the hostility item of the Positive and Negative Syndrome Scale (PANSS P7) and the disturbing and aggressive behaviour domain of the Personal and Social Performance scale (PSP-D).

RESULTS

Moderate, severe or extreme hostility (PANSS P7 > 3) was present in 42 patients (9.4%). The PANSS P7 and PSP-D were low to moderate but significantly associated with the selected PANSS items: delusions, hallucinatory behaviour, excitement, tension, uncooperativeness, unusual thought content, impulsivity, and lack of judgement and insight. In a subsample of 185 patients (41.5%) with baseline PANSS P7 > 1, the PANSS P7 and PSP-D scores improved in the first 4 weeks of amisulpride treatment. This effect remained significant after controlling for baseline positive symptoms (PANSS P1-P6). No significant differences were found between olanzapine and amisulpride in the second phase of the trial.

CONCLUSION

Clinical risk factors such as poor impulse control, uncooperativeness and excitement could help clinicians in detecting and treating hostile and aggressive behaviour in FEP. Amisulpride could be an effective antipsychotic choice in the treatment of FEP patients who express hostile or aggressive behaviour. Future research is needed to compare the effects of amisulpride and olanzapine on hostility in FEP during the first weeks of treatment.

A rapid FTIR spectroscopic assay for quantitative determination of Memantine hydrochloride and Amisulpride in human plasma and pharmaceutical formulations

A selective, new, rapid and nondestructive Fourier transform Infrared spectroscopic assay has been developed for simultaneous determination of Memantine hydrochloride and Amisulpride in human plasma and their pharmaceutical formulations without interference from common dugs excipients. A binary mixture of ME and nonselective β-blocker namely; carvidalol has been determined the solid-state by FTIR spectroscopy for the first time. The linear range had been extent from 1.0 to 8.0 and 1.0 to 10.0 μg/mg, for ME and AMS respectively. The detection limits were 0.29 and 0.23 μg/mg while quantitation limits were 0.90 and 0.71 μg/mg for ME and AMS respectively. The developed assay has been validated according to ICH & USP recommendations and successfully applied for quantitative determination of selected drugs in biological fluid.

A pharmacological profile of intravenous amisulpride for the treatment of postoperative nausea and vomiting

INTRODUCTION

The issue of postoperative nausea and vomiting (PONV) remains important in surgical practice, contributing to patient distress, slower recovery, and increased use of healthcare resources. Many surgical patients report it to be a worse problem than the pain. New antiemetics of different classes are still needed to help manage PONV effectively, especially the treatment of established PONV after the failure of common prophylactic antiemetics such as 5-HT₃-antagonists and corticosteroids. Intravenous amisulpride, a drug with a long history of safe use in oral form as an antipsychotic, has recently been approved in the US (trade name: Barhemsys) as an intravenous antiemetic for the prevention and treatment of PONV.

AREAS COVERED

This review article summarizes the published data on the clinical pharmacology, safety, and efficacy of intravenous amisulpride as an antiemetic, supplemented by published data on oral amisulpride, where relevant to the intravenous form. Literature was obtained via the PubMed search terms 'intravenous amisulpride' and 'amisulpride AND safety.' Both primary and secondary pharmacology are covered, along with clinical pharmacokinetics (distribution, metabolism, and excretion). The review of clinical safety and efficacy includes data from four studies in the prevention of PONV, two in the treatment of PONV and two investigating effects on the QT interval of the electrocardiogram in healthy volunteers.

EXPERT OPINION

Given the importance of sufficient PONV prevention for patients and the healthcare system, the availability of intravenous amisulpride is helpful, restoring the dopamine-antagonist class as a potential mainstay in both combination prophylaxis and treatment.

Efficacy of amisulpride on postoperative nausea and vomiting: a systematic review and meta-analysis

AIM AND BACKGROUND

Postoperative nausea and vomiting (PONV) remains a significant clinical problem for surgical patients. Amisulpride is a well-studied D_2/D₃ antagonist that has the potential to be used for preventing and treating PONV. Our aim was to assess the efficacy and safety of amisulpride for prevention and treatment of PONV through a systematic review and meta-analysis.

METHOD

A systematic literature search was performed using MEDLINE, EMBASE, PUBMED, clinicaltrials.gov, and the Cochrane Central Register of Controlled Trials from their inception to Feb 15th, 2019. The efficacy outcome was the incidence of complete response, defined as no emesis and no rescue antiemetic use in a 24-h period after study drug administration. The safety outcomes were the adverse effects associated with amisulpride.

RESULTS

Five studies comprising 3243 patients met inclusion critieria. Compared with placebo, amisulpride showed a significantly improved incidence of complete response [relative risk (RR): 1.30; 95% confidence interval (CI): 1.20-1.41; P < 0.00001, I² = 0%] with firm evidence from the trial sequential analysis. Particularly, the amisulpride at 5 mg dose indicated a significant benefit than placebo [relative risk (RR): 1.28; 95% confidence interval (CI): 1.18-1.39; P < 0.00001, I² = 4%]. The adverse event profile of amisulpride was generally similar to the placebo.

CONCLUSION

Based on our findings, low-dose, intravenous amisulpride is safe and efficacious for the prevention and treatment of PONV compared to placebo. Further studies are needed to explore the optimal dose and timing.

CLINICAL TRIAL REGISTRATION

PROSPERO: CRD42019121483.

A randomized double-blind controlled trial to assess the benefits of amisulpride and olanzapine combination treatment versus each monotherapy in acutely ill schizophrenia patients (COMBINE): methods and design

This report presents the rationale and design of a multi-center clinical trial that examines the efficacy and safety of antipsychotic combination treatment in acutely ill schizophrenia patients compared to antipsychotic monotherapy. Antipsychotic combination treatment is common in clinical practice worldwide, despite clinical guidelines generally not recommending such practice due to lacking evidence for its efficacy and safety. Olanzapine has a related chemical structure and comparable receptor-binding profile as clozapine, which demonstrated superior efficacy in combination studies, but has a more unfavorable side-effect profile compared to olanzapine. Amisulpride and olanzapine have shown promising therapeutic efficacy in meta-analyses in monotherapy for people with schizophrenia. Combining amisulpride and olanzapine, complementary receptor-binding properties may enhance efficacy and possibly reduce (or at least not augment) side effects due to the different receptor profiles and metabolization pathways. Accordingly, we hypothesize that patients treated with amisulpride plus olanzapine show greater improvement on the Positive and Negative Syndrome Scale total score after 8 weeks versus either monotherapy. A randomized, double-blind controlled trial is performed at 16 German centers comparing flexibly dosed monotherapy of oral amisulpride (400-800 mg/day), and olanzapine (10-20 mg/day) and amisulpride-olanzapine co-treatment. Sample size was calculated to be n = 101 per treatment arm, assuming an effect size of 0.500 and a two-sided alpha = 0.025 and beta = 0.90. Recruitment for this trial started in June 2012. Until December 2018, 328 patients have been randomized. Trial conduct has been extended to reach the projected sample size. Publication of the study results is expected in 2019 informing an evidence-based recommendation regarding specific antipsychotic combination treatment.

A new spectrofluorimetric assay for quantification of Amisulpride and Memantine hydrochloride in real human plasma sample and pharmaceutical formulations via Hantzsch reaction

A new, selective and accurate spectrofluorimetric assay has been described for detection of Amisulpride and Memantine hydrochloride in pharmaceutical formulations and real plasma samples. The described assay depends on the reaction between the primary amino group of the selected drugs with acetyl acetone & formaldehyde in an acetate buffer of pH4.8. The derivatized product showed yellow fluorescence at λ_ex=418nm and λ_em=484.5nm. The calibration graph was linear in the range of 0.05-0.5 and 0.2-1μgmL^-1 for AMS and ME, orderly. The limits of detection were 0.0085 and 0.0153μgmL^-1, and the limits of quantitation were 0.026 and 0.0464μgmL^-1 for AMS and ME respectively. Validation of the described assay was in consonance with ICH guideline. Due to the sensitivity of the prescribed assay, it permits the determination of selected medications in biological sample quantitatively.

Microenvironmental pH-modified Amisulpride-Labrasol matrix tablets: development, optimization and in vivo pharmacokinetic study

Amisulpride (AMS) is atypical antipsychotic with a weak basic nature (pKa 9.37), which results in low solubility in the high pH of the intestine. It is also recognized as a substrate of P-glycoprotein efflux pump. Both factors lead to its low oral bioavailability (48%). The daily dose of AMS is between 200 and 1200 mg to be taken in divided doses which compromise patient compliance. Therefore, controlled release formulation of AMS is of clinical significance. AMS was formulated into matrix tablets containing Labrasol, P-glycoprotein efflux inhibitor, and a penetration enhancer, using direct compression technique. The tablets were prepared according to 2¹·4¹ factorial design using two polymers, namely, HPMC and Carbopol 934 at four concentrations (20%, 30%, 40%, 50%). Percentage AMS released after 2 h (Q_2hr%) and 8 h (Q_8hr%) were chosen as dependent variables. Two acidic pH modifiers (fumaric acid and tartaric acid) at two levels (15% and 30%) were incorporated in the tablet according to 2² factorial design. All formulae with acidic pH modifier had similarity factor (f₂) ≥ 50 proving the pH independent release of AMS. The pharmacokinetic study in rabbits revealed 30% enhancement of the oral absorption AMS imparted by the pH-modified matrix tablet containing Labrasol. Graphical abstract.

Region-specific blood-brain barrier transporter changes leads to increased sensitivity to amisulpride in Alzheimer's disease

BACKGROUND

Research into amisulpride use in Alzheimer's disease (AD) implicates blood-brain barrier (BBB) dysfunction in antipsychotic sensitivity. Research into BBB transporters has been mainly directed towards the ABC superfamily, however, solute carrier (SLC) function in AD has not been widely studied. This study tests the hypothesis that transporters for organic cations contribute to the BBB delivery of the antipsychotics (amisulpride and haloperidol) and is disrupted in AD.

METHODS

The accumulation of [3H]amisulpride (3.7-7.7 nM) and [3H]haloperidol (10 nM) in human (hCMEC/D3) and mouse (bEnd.3) brain endothelial cell lines was explored. Computational approaches examined molecular level interactions of both drugs with the SLC transporters [organic cation transporter 1 (OCT1), plasma membrane monoamine transporter (PMAT) and multi-drug and toxic compound extrusion proteins (MATE1)] and amisulpride with the ABC transporter (P-glycoprotein). The distribution of [3H]amisulpride in wildtype and 3×transgenic AD mice was examined using in situ brain perfusion experiments. Western blots determined transporter expression in mouse and human brain capillaries .

RESULTS

In vitro BBB and in silico transporter studies indicated that [3H]amisulpride and [3H]haloperidol were transported by the influx transporter, OCT1, and efflux transporters MATE1 and PMAT. Amisulpride did not have a strong interaction with OCTN1, OCTN2, P-gp, BCRP or MRP and could not be described as a substrate for these transporters. Amisulpride brain uptake was increased in AD mice compared to wildtype mice, but vascular space was unaffected. There were no measurable changes in the expression of MATE1, MATE2, PMAT OCT1, OCT2, OCT3, OCTN1, OCTN2 and P-gp in capillaries isolated from whole brain homogenates from the AD mice compared to wildtype mice. Although, PMAT and MATE1 expression was reduced in capillaries obtained from specific human brain regions (i.e. putamen and caudate) from AD cases (Braak stage V-VI) compared to age matched controls (Braak stage 0-II).

CONCLUSIONS

Together our research indicates that the increased sensitivity of individuals with Alzheimer's to amisulpride is related to previously unreported changes in function and expression of SLC transporters at the BBB (in particular PMAT and MATE1). Dose adjustments may be required for drugs that are substrates of these transporters when prescribing for individuals with AD.

A cost-utility analysis of Amisulpride and Paliperidone in the treatment of Schizophrenia

Background

Schizophrenia is a severe, long-term neurodevelopmental disorder that results in increased morbidity and mortality. Amisulpride and Paliperidone are two antipsychotics used to treat schizophrenia in the UK. This evaluation compares the cost-utility of each drug; no similar research has been conducted in the UK.

Methods

A cost utility analysis was performed looking at the benefits in terms of Quality Adjusted Life Years within one year of the treatment, and the costs in pound sterling, discounted to the 2016/2017 value. This evaluation was from the perspective of the National Health Service, the biggest provider of health within the United Kingdom.

Outcomes

The cost utility analysis found an incremental cost effectiveness ratio of £10,941 per added Quality Adjusted Life Year for using Paliperidone, instead of the more widely used Amisulpride.

Interpretation

This is below the NICE threshold of £20–30,000 per QALY. Hence, it is within reason to suggest shifting diagnostic practices to Paliperidone.

Computational modelling reveals contrasting effects on reinforcement learning and cognitive flexibility in stimulant use disorder and obsessive-compulsive disorder: remediating effects of dopaminergic D2/3 receptor agents

RATIONALE

Disorders of compulsivity such as stimulant use disorder (SUD) and obsessive-compulsive disorder (OCD) are characterised by deficits in behavioural flexibility, some of which have been captured using probabilistic reversal learning (PRL) paradigms.

OBJECTIVES

This study used computational modelling to characterise the reinforcement learning processes underlying patterns of PRL behaviour observed in SUD and OCD and to show how the dopamine D2/3 receptor agonist pramipexole and the D2/3 antagonist amisulpride affected these responses.

METHODS

We applied a hierarchical Bayesian method to PRL data across three groups: individuals with SUD, OCD, and healthy controls. Participants completed three sessions where they received placebo, pramipexole, and amisulpride, in a double-blind placebo-controlled, randomised design. We compared seven models using a bridge sampling estimate of the marginal likelihood.

RESULTS

Stimulus-bound perseveration, a measure of the degree to which participants responded to the same stimulus as before irrespective of outcome, was significantly increased in SUD, but decreased in OCD, compared to controls (on placebo). Individuals with SUD also exhibited reduced reward-driven learning, whilst both the SUD and OCD groups showed increased learning from punishment (nonreward). Pramipexole and amisulpride had similar effects on the control and OCD groups; both increased punishment-driven learning. These D2/3-modulating drugs affected the SUD group differently, remediating reward-driven learning and reducing aspects of perseverative behaviour, amongst other effects.

CONCLUSIONS

We provide a parsimonious computational account of how perseverative tendencies and reward- and punishment-driven learning differentially contribute to PRL in SUD and OCD. D2/3 agents modulated these processes and remediated deficits in SUD in particular, which may inform therapeutic effects.

A new sensitive approach for spectrofluorimetric assay of Milnacipran and Amisulpride in real plasma and pharmaceutical preparations via complexation with Eosin Y dye

An accurate, economic, rapid, reliable spectrofluorimetric assay was developing for the assay of definite anti-depressant drugs namely Amisulpride and Milnacipran hydrochloride, in those pharmaceutical preparation and biological fluid. The suggested method was established on the detection of quenching process resulting from the action of AMS and MCN to the native fluorescent EosinY. A binary complex between selected medications and Eosin Y was established in acetate buffer (0.2 M) at pH 3.3 & 4.0 for AMS and MCN respectively. The relative fluorescence capacity was determined at λex = 301.8 nm and λem = 542.7 nm. The calibration graphs had been linear through extent from 0.02 to 0.3 and 0.1-1 μg mL^-1, to both dugs respectively. Detection limits have been 0.0047 & 0.0188 μg mL^-1 while quantitation limits have been 0.0141 & 0.0569 μg mL^-1 to AMS & MCN respectively. Developed assay has been validated in agreement with ICH recommendations. Due to high sensitivity of the described assay, it allows the quantitation of anti-depressant drugs through biological fluid.

c-Fos expression response to olanzapine, amisulpride, aripiprazole, and quetiapine single administration in the rat forebrain: Effect of a mild stress preconditioning

Antipsychotics have been shown to stimulate different forebrain areas, whereas some of them are sensitive to stress. In the present study, effect of a single administration of olanzapine (OLA), amisulpride (AMI), aripiprazole (ARI), and quetiapine (QUE) on the activity of cells in the striatal dorsolateral (stDL) area, the periventricular zone (peVZ), the septal ventrolateral (seVL) nucleus, and the accumbens nucleus shell (shACC) and core (coACC) was investigated in male rats preconditioned with a mild stress complex (CMS) for 20 days. The objective of the study was to extend the anatomical-functional knowledge on the mechanism of selected antipsychotics with the goals: 1) to analyze the ability of the selected antipsychotics to induce c-Fos protein expression in the above mentioned forebrain structures and to map the pattern of their topography and 2) to find out whether longer-lasting mild stress preconditioning may modify the impact of the selected antipsychotics on the activity of cells in the forebrain areas in adult rats. Ten groups of rats were used. CMS complex contained five stressors: cage crowding, air-puff noising, wet bedding, predator stress, and forced swimming. AMI (20 mg/kg), OLA (5 mg/kg), QUE (15 mg/kg), and ARI (10 mg/kg/b.w.) were administered intraperitoneally and 90 min later the animals transcardially perfused by fixative. c-Fos was visualized by ABC complex. In unstressed animals, OLA and ARI elevated c-Fos expression in all areas studied, AMI and QUE in all areas except stDL, seVL and coACC, shACC FL-2 (shACC posterior level), respectively. CMS potentiated the effect of AMI in coACC, and QUE in shACC FL-2 and suppressed the effect of AMI in peVZ, and ARI in peVZ and seVL. The present data provide new insights into activity of cells in response to CMS challenge, which might be helpful in understanding the diverse clinical effects of atypical antipsychotics.

Dopaminergic drug treatment remediates exaggerated cingulate prediction error responses in obsessive-compulsive disorder

RATIONALE

Patients with obsessive-compulsive disorder (OCD) have been found to show exaggerated error responses and prediction error learning signals in a variety of EEG and fMRI tasks, with data converging on the anterior cingulate cortex as a key locus of dysfunction. Considerable evidence has linked prediction error processing to dopaminergic function.

OBJECTIVE

In this study, we investigate potential dopaminergic dysfunction during reward processing in the context of OCD.

METHODS

We studied OCD patients (n = 18) and controls (n = 18) whilst they learned probabilistic associations between abstract stimuli and monetary rewards in the fMRI scanner involving administration (on separate visits) of a dopamine receptor agonist, pramipexole 0.5 mg; a dopamine receptor antagonist, amisulpride 400 mg; and placebo. We fitted a Q-learning computational model to fMRI prediction error responses; group differences were examined in anterior cingulate and nucleus accumbens regions of interest.

RESULTS

There were no significant group, drug, or interaction effects in the number of correct choices; computational modeling suggested a marginally significant difference in learning rates between groups (p = 0.089, partial ƞ² = 0.1). In the imaging results, there was a significant interaction of group by drug (p = 0.013, partial ƞ² = 0.13). OCD patients showed abnormally strong cingulate signaling of prediction errors during omission of an expected reward, with unexpected reduction by both pramipexole and amisulpride (p = 0.014, partial ƞ² = 0.26, 1-β error probability = 0.94). Exaggerated cingulate prediction error signaling to omitted reward in placebo was related to trait subjective difficulty in self-regulating behavior in OCD.

CONCLUSIONS

Our data support cingulate dysfunction during reward processing in OCD, and bidirectional remediation by dopaminergic modulation, suggesting that exaggerated cingulate error signals in OCD may be of dopaminergic origin. The results help to illuminate the mechanisms through which dopamine receptor antagonists achieve therapeutic benefit in OCD. Further research is needed to disentangle the different functions of dopamine receptor agonists and antagonists during bidirectional modulation of cingulate activation.

Comparative efficacy and safety between amisulpride and olanzapine in schizophrenia treatment and a cost analysis in China: a systematic review, meta-analysis, and cost-minimization analysis

BACKGROUND

Amisulpride was introduced into China in 2010 as a second-generation atypical antipsychotic, while olanzapine has been on the market since 1999 as one of the leading treatments for schizophrenia in China. Since more Chinese patients are gaining access to amisulpride, the study aims to compare the efficacy, safety, and costs between amisulpride and olanzapine for schizophrenia treatment in China.

METHODS

PubMed, Embase, the Cochrane library, China National Knowledge Infrastructure (CNKI) and WanFang database were systematically searched for randomized controlled trials (RCTs) up to July 2018. The Cochrane Risk of Bias tool was utilized to assess the quality of included studies. A meta-analysis was performed to compare the efficacy and safety of amisulpride and olanzapine, followed by a cost-minimization analysis using local drug and medical costs reported in China.

RESULTS

Twenty RCTs with 2000 patients were included in the systematic review. There were no significant differences between amisulpride and olanzapine on efficacy measures based on scores from the Positive and Negative Syndrome Scale, the Scale for the Assessment of Negative Symptoms, the Brief Psychiatric Rating Scale and the Clinical Global Impressions-Severity or Improvement. For safety outcomes, amisulpride was associated with lower fasting blood glucose and less abnormal liver functions as well as significantly lower risks of weight gain, constipation, and somnolence; olanzapine was associated with significantly lower risks of insomnia and lactation/amenorrhea/sexual hormone disorder. No significant differences were found in risks of extrapyramidal symptoms (EPS), tremor, akathisia, abnormal corrected QT interval. Cost-minimization analysis showed that amisulpride was likely to be a cost-saving alternative in China, with potential savings of 1358 Chinese Yuan (CNY) per patient for a three-month schizophrenia treatment compared with olanzapine.

CONCLUSION

As the first meta-analysis and cost-minimization analysis comparing the efficacy, safety and cost of amisulpride and olanzapine within a Chinese setting, the study suggests that amisulpride may be an effective, well-tolerated, and cost-saving antipsychotic drug alternative in China.

Ventricular Arrhythmia during Tracheal Intubation and Extubation under General Anesthesia Possibly Induced by Amisulpride: A Case Report

We are presenting the first documented case of amisulpride related ventricular arrhythmia during tracheal intubation and extubation under general anesthesia in an 48 year-old female with psychiatric history of chronic schizophrenia who was treated with amisulpride. This case suggests the threshold of perioperative arrhythmia is possibly decreased in patients with long-term antipsychotic medication. So, the potential risk of antipsychotics-induced perioperative arrhythmia should be evaluated, as well as heart rhythm monitoring, prophylactic use of antiarrhythmic drugs, and preoperative adjustment of antipsychotics should be considered.

White matter integrity associated with severity reductions in positive symptoms after amisulpride treatment in drug-free patients with schizophrenia

Amisulpride is an effective antipsychotic for the treatment of schizophrenia with a lower propensity for extrapyramidal adverse effects than conventional antipsychotics. However, no study has investigated white matter (WM) integrity in patients with schizophrenia in relation to treatment response after amisulpride administration. Here, we investigated the associations of WM integrity with severity reductions in clinical symptoms in drug-free patients with schizophrenia at an early stage of amisulpride treatment. Nineteen patients with schizophrenia (SZ) and 15 healthy controls (HCs) participated in the present study. Diffusion tensor imaging data were acquired from all participants at baseline. All SZ participants began treatment with 200 mg of amisulpride per day. The dose was increased up to 1200 mg/day within 2 weeks depending on the severity of clinical symptoms, and maintained for the subsequent 6 weeks. Initially, and after 8 weeks of amisulpride treatment, SZ participants were assessed for the severity of overall illness, positive and negative symptoms, and motor side effects. SZ participants showed lower integrity in several WM regions, including the corpus callosum and fronto-temporal connections, when compared to HCs. Furthermore, lower WM integrity in fronto-temporo-limbic regions at baseline was found to be associated with severity reductions in positive symptoms after 8 weeks. Our findings suggest that WM integrity at the early stage of treatment may serve as a possible predictive marker for treatment response.

Quetiapine Related Acute Paralytic Ileus in a Bipolar I Disorder Patient with Successful Low Dose Amisulpride Substitution: A Case Report

The mechanism of medication-induced gastrointestinal hypomotility is primarily caused by muscarinic cholinergic antagonism. This effect may cause constipation and paralytic ileus, which may lead to fatal complications. A 51-year-old woman was admitted due to manic episode recurrence. She developed paralytic ileus under quetiapine use and treated successfully under low dose amisulpride use. The related mechanism, associated risk factors, and the rationale for medication switch are discussed.

Resolution V fractional factorial design for screening of factors affecting weakly basic drugs liposomal systems

This study aims to investigate factors affecting weakly basic drugs liposomal systems. Resolution V fractional factorial design (2_V^5-1) is used as an example of screening designs that would better be used as a wise step before proceeding with detailed factors effects or optimization studies. Five factors probable to affect liposomal systems of weakly basic drugs were investigated using Amisulpride as a model drug. Factors studied were; A: Preparation technique B: Phosphatidyl choline (PhC) amount (mg) C: Cholesterol: PhC molar ratio, D: Hydration volume (ml) and E: Sonication type. Levels investigated were; Ammonium sulphate-pH gradient technique or Transmembrane zinc chelation-pH gradient technique, 200 or 400 mg, 0 or 0.5, 10 or 20 ml and bath or probe sonication for A, B, C, D and E respectively. Responses measured were Particle size (PS) (nm), Zeta potential (ZP) (mV) and Entrapment efficiency percent (EE%). Ion selective electrode was used as a novel method for measuring unentrapped drug concentration and calculating entrapment efficiency without the need for liposomal separation. Factors mainly affecting the studied responses were Cholesterol: PhC ratio and hydration volume for PS, preparation technique for ZP and preparation technique and hydration volume for EE%. The applied 2_V^5-1 design enabled the use of only 16 trial combinations for screening the influence of five factors on weakly basic drugs liposomal systems. This clarifies the value of the use of screening experiments before extensive investigation of certain factors in detailed optimization studies.

Amisulpride Reexposure and Tardive Dyskinesia

To highlight the association between amisulpride and onset of tardive dyskinesia (TD) in patient suffering with psychosis not otherwise specified (NOS), who has already been treated with amisulpride for many years. A 40-year-old female suffering with psychosis NOS since 19 years presented with recurrence of positive symptoms in the form of delusion of persecution, ideas of grandiosity since last 3 months. She was treated with amisulpride up to 400 mg/day and developed involuntary oro-buccal-lingual movement within 2 months of amisulpride therapy. Amisulpride an atypical antipsychotic can lead to the development of TD in patient who already received amisulpride for many years in the past. Reexposure with amisulpride can lead to early onset of TD due to blockade of already unregulated postsynaptic supersensitive dopamine receptors.

Discriminative stimulus properties of the atypical antipsychotic amisulpride: comparison to its isomers and to other benzamide derivatives, antipsychotic, antidepressant, and antianxiety drugs in C57BL/6 mice

RATIONALE

Racemic (RS)-amisulpride (Solian^®) is an atypical antipsychotic drug used to treat schizophrenia and dysthymia. Blockade of dopamine D₂/D₃ and/or serotonin 5-HT₇ receptors is implicated in its pharmacological effects. While the (S)-amisulpride isomer possesses a robust discriminative cue, discriminative stimulus properties of (RS)-amisulpride have not been evaluated.

OBJECTIVES

The present study established (RS)-amisulpride as a discriminative stimulus and assessed amisulpride-like effects of amisulpride stereoisomers, other benzamide derivatives, and antipsychotic, antidepressant, and anxiolytic drugs.

METHODS

Adult, male C57BL/6 mice were trained to discriminate 10 mg/kg (RS)-amisulpride from vehicle in a two-lever food-reinforced operant conditioning task.

RESULTS

(RS)-Amisulpride's discriminative stimulus was dose-related, time-dependent, and stereoselective. (S)-Amisulpride (an effective dose of 50% (ED₅₀) = 0.21 mg/kg) was three times more potent than (RS)-amisulpride (ED₅₀ = 0.60 mg/kg) or (R)-amisulpride (ED₅₀ = 0.68 mg/kg). (RS)-Amisulpride generalized fully to the structurally related atypical antipsychotic/antidysthymia drug sulpiride (Sulpor^®; ED₅₀ = 7.29 mg/kg) and its (S)-enantiomer (ED₅₀ = 9.12 mg/kg); moderate to high partial generalization [60-75% drug lever responding (%DLR)] occurred to the benzamide analogs tiapride (Tiapridal^®) and raclopride, but less than 60% DLR to metoclopramide (Reglan^®), nemonapride (Emilace^®), and zacopride. Antipsychotic, antidepressant, and antianxiety drugs from other chemical classes (chlorpromazine, quetiapine, risperidone, and mianserin) produced 35-55% amisulpride lever responding. Lastly, less than 35% DLR occurred for clozapine, olanzapine, aripiprazole imipramine, chlordiazepoxide, and bupropion.

CONCLUSIONS

(RS)-Amisulpride generalized to some, but not all benzamide derivatives, and it failed to generalize to any other antipsychotic, antidepressant, or antianxiety drugs tested. Interestingly, the (R)-isomer shared very strong stimulus properties with (RS)-amisulpride. This finding was in contrast to findings from Donahue et al. (Eur J Pharmacol 734:15-22, 2014), which found that the (R)-isomer did not share very strong stimulus properties when the (S)-isomer was the training drug.

Noradrenergic modulation of neural erotic stimulus perception

We recently investigated neuromodulatory effects of the noradrenergic agent reboxetine and the dopamine receptor affine amisulpride in healthy subjects on dynamic erotic stimulus processing. Whereas amisulpride left sexual functions and neural activations unimpaired, we observed detrimental activations under reboxetine within the caudate nucleus corresponding to motivational components of sexual behavior. However, broadly impaired subjective sexual functioning under reboxetine suggested effects on further neural components. We now investigated the same sample under these two agents with static erotic picture stimulation as alternative stimulus presentation mode to potentially observe further neural treatment effects of reboxetine. 19 healthy males were investigated under reboxetine, amisulpride and placebo for 7 days each within a double-blind cross-over design. During fMRI static erotic picture were presented with preceding anticipation periods. Subjective sexual functions were assessed by a self-reported questionnaire. Neural activations were attenuated within the caudate nucleus, putamen, ventral striatum, the pregenual and anterior midcingulate cortex and in the orbitofrontal cortex under reboxetine. Subjective diminished sexual arousal under reboxetine was correlated with attenuated neural reactivity within the posterior insula. Again, amisulpride left neural activations along with subjective sexual functioning unimpaired. Neither reboxetine nor amisulpride altered differential neural activations during anticipation of erotic stimuli. Our results verified detrimental effects of noradrenergic agents on neural motivational but also emotional and autonomic components of sexual behavior. Considering the overlap of neural network alterations with those evoked by serotonergic agents, our results suggest similar neuromodulatory effects of serotonergic and noradrenergic agents on common neural pathways relevant for sexual behavior.

Amisulpride withdrawal dyskinesia: a case report

BACKGROUND

The effects of antipsychotic drug withdrawal have been inadequately studied. Case reports have described dyskinesia occurring in patients with several antipsychotics withdrawn, but studies on amisulpride withdrawal dyskinesia are lacking.

CASE PRESENTATION

A 63-year-old man, who was diagnosed with schizophrenia at age 49, received amisulpride treatment since age 62. The dosage of amisulpride was reduced from 200 to 50 mg/day because of occurrence of akathisia during one admission. Severe withdrawal dyskinesia, mixed with dystonia and akathisia, was noted immediately after the dosage reduction. The abnormal involuntary movement showed improvement 2 weeks later when the dosage was increased to 100 mg/day.

CONCLUSIONS

Withdrawal dyskinesia and other abnormal involuntary movements could be noted in a patient with reduction of amisulpride dosage or sudden termination. Withdrawal dyskinesia may subsequently lead to persistent tardive dyskinesia. Therefore, withdrawal-emergent dyskinesia should be promptly identified, and appropriate medical interventions should be given early.