Quetiapine (Seroquel) is an antipsychotic that treats schizophrenia and bipolar disorder. It balances dopamine and serotonin in your brain. Quetiapine is one of only two antipsychotics (the other is cariprazine) that produce equal efficacy as standalone therapies for mixed manic-depressive mood swings as they do in combination with an SSRI antidepressant. Detailed dosage guidelines and administration information for Seroquel (quetiapine fumarate). Includes dose adjustments, warnings and precautions. Seroquel (quetiapine) is an atypical antipsychotic medication used to treat mental disorders such as depression. Doctors also prescribe it off-label to treat anxiety disorders. Quetiapine is used alone or together with other medicines to treat bipolar disorder (depressive and manic episodes) and schizophrenia. Quetiapine extended-release tablet is also used together with other antidepressants to treat major depressive disorder. Seroquel is a prescription medicine used to treat the symptoms of Schizophrenia, Bipolar I Disorder, Mania; Bipolar Disorder, Depressive Episodes; Bipolar I Disorder, Maintenance; and Major Depressive Disorder. Seroquel may be used alone or with other medications. Adjunctive treatment of major depressive disorder. This means quetiapine is used in addition to an antidepressant to help treat depression. This medication sheet will focus primarily on schizophrenia. You can find more information about bipolar disorder and depression here. SEROQUEL XR is a once-daily tablet approved in adults for add-on treatment to antidepressants for patients with major depressive disorder (MDD) who did not have an adequate response to antidepressant therapy; Seroquel is used to treat the symptoms of schizophrenia, bipolar disorder and major depressive disorder. Learn about side effects, interactions and indications. Find patient medical information for Quetiapine (Seroquel) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings.