Key takeaways
Quetiapine (Seroquel) and olanzapine (Zyprexa) are both atypical antipsychotics used to treat schizophrenia and bipolar disorder. Quetiapine is available in both immediate-release and extended-release forms, while olanzapine can be taken as a tablet or an injection. Quetiapine is also used as an add-on treatment for depression, whereas olanzapine is combined with fluoxetine (Prozac) for treating bipolar depression and treatment-resistant depression. Both medications can cause sleepiness and dizziness, as well as more serious side effects including higher risk of death in older people with dementia-related psychosis and neuroleptic malignant syndrome. Quetiapine needs to be taken multiple times a day in its immediate-release form, while olanzapine is typically taken once daily. Both medications are available as a low-cost generic
