Olanzapine is used to treat certain mental/mood conditions (such as schizophrenia, bipolar disorder). It may also be used in combination with other medication to treat depression. In schizophrenia, Zyprexa tablets have been studied in about 3,000 adults, in which their effectiveness was compared with that of placebo (a dummy treatment) or haloperidol (another antipsychotic medicine). Zyprexa, the brand name for olanzapine, is an atypical antipsychotic that has been available in the United States for about twenty years. Structurally similar to clozapine (sold as Clozaril in the U.S.), Zyprexa is known to be an effective antipsychotic that also offers some efficacy as an adjunct in the treatment of depression. How to use Zyprexa. Read the Medication Guide provided by your pharmacist before you start taking olanzapine and each time you get a refill. If you have any questions, ask your doctor or pharmacist. Only your healthcare provider can determine the length of olanzapine treatment that is right for you. Missing doses of olanzapine may increase your risk for a relapse in your symptoms. Do not stop taking olanzapine or change your dose without talking to with your healthcare provider first. Schizophrenia. Oral Zyprexa is indicated for the treatment of schizophrenia. Efficacy was established in three clinical trials in adult patients with schizophrenia: two 6-week trials and one maintenance trial. Zyprexa is an antipsychotic medication that affects chemicals in the brain. Zyprexa is used to treat the symptoms of psychotic conditions such as schizophrenia and the symptoms of mood disorders such as bipolar disorder (manic depression) in adults and children who are at least 13 years old. Zyprexa is the brand name of olanzapine, a prescription drug used to treat schizophrenia and bipolar disorder. It's also used to treat depression when used with other medications. Zyprexa may interact with other medicines that can make you sleepy or slow your breathing (such as cold or allergy medicines, narcotic pain medicines, sleeping pills, muscle relaxers, and medicines for depression, seizure, anxiety), and heart or blood pressure medications. The recommended starting dose of Zyprexa Velotab depends on the disease being treated: 10 mg per day is used in schizophrenia and in the prevention of manic episodes, and 15 mg per day in the treatment of manic episodes, unless it is used with other medicines, in which case the starting dose can be 10 mg per day.