Since 1990, the arsenal of psychotropic ...

Since 1990, the arsenal of psychotropic drugs used to treat schizophrenia, appear New drugs - atypical antipsychotics. Unlike the previous generation of drugs (classical or typical neuroleptics), atypical antipsychotics show significant efficacy primarily in the correction of the negative manifestations of schizophrenia. Also, virtually conceding typical neuroleptics in its effect on positive symptoms, atypical drugs are characterized by More and more favorable tolerability profile, in a structure which extrapyramidal side effects occupy an insignificant place, or non-existent. In Russia, registered with atypical antipsychotics such as risperidone, olanzapine, quetiapine, ziprasidone, sertindole. In recent years, clinical trials and other members of the class drugs. The main mechanism of action of these drugs is associated, firstly, with the blockade of dopamine receptors (D2 subtype) in the mesolimbic system of the brain that causes their antipsychotic effect in the form of reduction of positive symptoms, and secondly, with the blockade of serotonin receptors (5 -HT2a subtype) in mezokortikalnoy system that, at the clinical level, expressed as the inverse dynamics of negative symptoms. Thus, in comparison with classical neuroleptics, the spectrum of neurochemical activity is limited influence on the dopaminergic system of the brain, atypical antipsychotic drugs act as a double action, since it has a balanced impact on both the dopamine and serotonin in the system. It is a double blockade neuroreceptors in the central nervous system and ultimately provides a positive impact on the two main groups of clinical manifestations of schizophrenia (positive and negative). Another important difference in the mechanism of action of atypical antipsychotics on the classical or typical neuroleptics was significantly lower affinity for D2-receptors. It is now known that more than 70% probability blockade of these receptors in the brain nigrostriarnoy system in most cases results in an excess of so-called neuroleptic threshold and the emergence, in addition to the antipsychotic effect adverse events in the form of various extrapyramidal disorders. This situation is typical for almost all typical neuroleptics. Having the same as it was said, a lower affinity for D2-receptors, while sufficient for the manifestation of anti-psychotic effects, atypical antipsychotics at therapeutic doses usually do not cause the aforementioned side effects. One of the earliest and most prominent representatives of the class of atypical antipsychotic is risperidone. This drug is the chemical structure relates to derivatives benzizoksazola. Risperidone is highly tropic to the serotonin 5-HT2-receptors, dopamine D2-receptors, also binds to a1-adrenoceptors and somewhat lower affinity histamine H1-receptors and a2-adrenoceptors.