Uses. This medication is used to treat certain mental/mood conditions (such as schizophrenia, bipolar disorder, sudden episodes of mania or depression associated with bipolar disorder). It is also used with other medications to treat depression. Quetiapine is known as an anti-psychotic drug (atypical type).ow to use Seroquel XR. Read the Medication Guide and, if available, the Patient Information Leaflet provided by your pharmacist before you start using quetiapine and each time you get a refill. If you have any questions, ask your doctor or pharmacist.