Amisulpride: progress and outcomes

Abstract

Amisulpride is a unique atypical antipsychotic that selectively blocks D2 and D3 receptors presynaptically in the frontal cortex, possibly enhancing dopaminergic transmission, and postsynaptically in the limbic areas, possibly reducing it. Thus dopaminergic over-activity in the frontal cortex, and under-activity in the limbic areas, can be treated simultaneously, alleviating both positive and negative symptoms of schizophrenia, respectively. In acute schizophrenia, amisulpride is at least as effective as haloperidol, with a greater number of patients responding to treatment as determined by Clinical Global Impression (CGI scores (p = 0.014). In addition, amisulpride is associated with a lower incidence of extrapyramidal symptoms (EPS) as determined by Simpson-Angus scores (SAS) when compared with haloperidol (p = 0.0053). Amisulpride showed similar efficacy to risperidone as determined by the Brief Psychiatric Rating Scale (BPRS) and the Positive and Negative Symptom Score (PANSS) positive subscale; a trend towards greater improvement of negative symptoms as determined by PANSS negative subscale compared with risperidone; and similar levels of EPS. Amisulpride uniquely benefits patients with negative symptoms and is the only antipsychotic to demonstrate efficacy in patients with predominantly negative symptoms. Amisulpride maintains its efficacy when used for medium/long-term treatment as demonstrated in studies of up to 12 months. Amisulpride demonstrates greater improvement in controlling symptoms compared to haloperidol. In terms of the relevance of the effects, a superiority is observed for quality of life, social adaptation and functioning as measured by the Quality of Life Scale (QLS), Clinical Glocal Impression scale (CGI) and Functional Status Questionnaire (FSQ) scales. Amisulpride also has one of the lowest potentials of all the antipsychotic agents for weight gain. The clinical evidence for amisulpride supports its earlier pre-clinical potential, showing it to be an atypical antipsychotic agent with specific clinical advantages.