Amisulpride

Amisulpride, sold under the brand name Solian among others, is an antipsychotic medication used to treat schizophrenia. It is also used to treat dysthymia. It is usually classed with the atypical antipsychotics. Chemically it is a benzamide and like other benzamide antipsychotics, such as sulpiride, it is associated with a high risk of elevating blood levels of the lactation hormone, prolactin (thereby potentially causing the absence of the menstrual cycle, breast enlargement, even in males, breast milk secretion not related to breastfeeding, impaired fertility, impotence, breast pain, etc.), and a low risk, relative to the typical antipsychotics, of causing movement disorders. It has also been found to be modestly more effective in treating schizophrenia than the typical antipsychotics. Amisulpride, sold under the brand name Solian among others, is an antipsychotic medication used to treat schizophrenia. It is also used to treat dysthymia. It is usually classed with the atypical antipsychotics. Chemically it is a benzamide and like other benzamide antipsychotics, such as sulpiride, it is associated with a high risk of elevating blood levels of the lactation hormone, prolactin (thereby potentially causing the absence of the menstrual cycle, breast enlargement, even in males, breast milk secretion not related to breastfeeding, impaired fertility, impotence, breast pain, etc.), and a low risk, relative to the typical antipsychotics, of causing movement disorders. It has also been found to be modestly more effective in treating schizophrenia than the typical antipsychotics. Amisulpride is believed to work by reducing signalling via the dopamine D2 receptor. In amisulpride's case this is by blocking, or antagonizing, the receptor. Amisulpride's effectiveness in treating dysthymia and the negative symptoms of schizophrenia is believed to stem from its blockade of the presynaptic dopamine D2 receptors. These presynaptic receptors regulate the release of dopamine into the synapse, so by blocking them amisulpride increases dopamine concentrations in the synapse. This increased dopamine concentration is theorized to act on dopamine D1 receptors to relieve depressive symptoms (in dysthymia) and the negative symptoms of schizophrenia. It was introduced by Sanofi-Aventis in the 1990s. Its patent had expired by 2008 and hence generic formulations are now available. It is marketed in all English-speaking countries except for Canada and the United States. In a 2013 study in a comparison of 15 antipsychotic drugs in effectiveness in treating schizophrenic symptoms, amisulpride was ranked second and demonstrated high effectiveness. 11% more effective than olanzapine (3rd), 32-35% more effective than haloperidol, quetiapine, and aripiprazole, and 25% less effective than clozapine (1st). Although according to other studies it appears to have comparable efficacy to olanzapine in the treatment of schizophrenia. Amisulpride augmentation, similarly to sulpiride augmentation, has been considered a viable treatment option (although this is based on low-quality evidence) in clozapine-resistant cases of schizophrenia. Another recent study concluded that amisulpride is an appropriate first-line treatment for the management of acute psychosis. Amisulpride's use is contraindicated in the following disease states Neither is it recommended to use amisulpride in patients with hypersensitivities to amisulpride or the excipients found in its dosage form. Hyperprolactinaemia results from antagonism of the D2 receptors located on the lactotrophic cells found in the anterior pituitary gland. Amisulpride has a high propensity for elevating plasma prolactin levels as a result of its poor blood-brain barrier penetrability and hence the resulting greater ratio of peripheral D2 occupancy to central D2 occupancy. This means that to achieve the sufficient occupancy (~60–80%) of the central D2 receptors in order to elicit its therapeutic effects a dose must be given that is enough to saturate peripheral D2 receptors including those in the anterior pituitary. The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotics to avoid acute withdrawal syndrome or rapid relapse. Symptoms of withdrawal commonly include nausea, vomiting, and loss of appetite. Other symptoms may include restlessness, increased sweating, and trouble sleeping. Less commonly there may be a felling of the world spinning, numbness, or muscle pains. Symptoms generally resolve after a short period of time. There is tentative evidence that discontinuation of antipsychotics can result in psychosis. It may also result in reoccurrence of the condition that is being treated. Rarely tardive dyskinesia can occur when the medication is stopped.