What is the primary class of the drugs clozapine, risperidone, olanzapine, and quetiapine?

Clozapine, risperidone, olanzapine, and quetiapine are classified as atypical antipsychotics. This class is characterized by their mechanism of action, which primarily involves antagonism at dopamine D2 receptors, but they also have significant effects on serotonin receptors, particularly 5-HT2A.

Atypical antipsychotics are known for their efficacy in treating both positive and negative symptoms of schizophrenia, and they tend to have a more favorable side effect profile compared to typical antipsychotics, such as haloperidol or chlorpromazine. Atypical antipsychotics have a lower risk of extrapyramidal symptoms (EPS), which are common with typical antipsychotics due to their stronger dopamine blockade. Moreover, some, like clozapine, are effective in treatment-resistant schizophrenia and can significantly reduce the risk of suicide in this patient population.

Understanding the distinction between atypical and typical antipsychotics is crucial for guiding treatment choices in psychiatric disorders, as well as for predicting potential side effects and patient outcomes.