Quetiapine

Quetiapine (/kwɪˈtaɪ.əpiːn/ kwi-TY-ə-peen), sold under the brand name Seroquel among others, is an atypical antipsychotic medication used in the treatment of schizophrenia, bipolar disorder, bipolar depression, and major depressive disorder. Despite being widely prescribed as a sleep aid due to its tranquillizing effects, the benefits of such use may not outweigh the risk of undesirable side effects. It is taken orally.

Common side effects include sedation, fatigue, weight gain, constipation, and dry mouth. Other side effects include low blood pressure with standing, seizures, high blood sugar, tardive dyskinesia, and neuroleptic malignant syndrome. In older people with dementia, its use increases the risk of death. Use in the third trimester of pregnancy may result in a movement disorder in the baby for some time after birth. Quetiapine is believed to work by blocking a number of receptors, including those for serotonin and dopamine.

Quetiapine was developed in 1985 and was approved for medical use in the United States in 1997. It is available as a generic medication. In 2022, it was the most prescribed antipsychotic and 82nd most commonly prescribed medication in the United States, with more than 8 million prescriptions. It is on the World Health Organization's List of Essential Medicines.

The drug is typically among two antipsychotics (the other being olanzapine) to have superior efficacy for the treatment of bipolar disorder. Quetiapine is currently one of only two antipsychotics (the other of which is cariprazine) that produce equal efficacy as a standalone therapy for mixed manic-depressive mood swings as it is when used in combination with an SSRI antidepressant. However, quetiapine is less potent than clozapine, amisulpride, olanzapine, risperidone, and paliperidone, respectively, in alleviating psychotic symptoms or treating schizophrenia.