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. The manufacturer of this medication has experienced several legal battles both ending in settlements: one regarding side effects and the withholding of information and the other regarding off label uses. See “Special Concerns” below for more information.
What is Zyprexa Prescribed for?
Zyprexa is approved by the FDA for use with psychotic disorders in adults and teens. This would include schizophrenia and bipolar disorder with psychotic features, as well as brief psychotic episodes. Olanzapine is also FDA approved for use with bipolar patients needing additional support in controlling acute manic episodes. Maintenance treatment with olanzapine for patients diagnosed with schizophrenia and use for depressive episodes in combination with Prozac are both approved uses. Zyprexa has been recommended to be approved for treating psychosis in children, but is not yet approved. The aforementioned approved uses are for children age 13 and older.
What does it do?
The precise way in which olanzapine works to help with psychotic symptoms is unknown. Some researchers theorize that it works on the dopamine and serotonin receptors, but the exact mechanism is not known.
However, due to the wide range and contradictory nature of side effects (for example, both restlessness and sedation may occur; sleepiness and insomnia may occur), it is thought that a number of different receptors are involved.
What are the Most Common Side Effects?
- Weight gain
- Restlessness and a feeling of needing to move, especially the legs, all the time
- Dryness, including dry mouth, constipation, urinary issues
- Daytime sleepiness; sedation
- Mood changes, including apathy and feeling numb or unable to feel happy
- Antipsychotic-related movement disorder (tardive dyskinesia)
The link between olanzapine and the raising of blood sugar has led to a label warning on all atypical antipsychotic medications informing patients of the risk of hyperglycemia and the possibility of developing diabetes. Weight gain with Zyprexa is common and the combination of weight gain, increases in blood sugar, and the development of diabetes is the most serious common side effect of using this medication.
The impact of taking olanzapine on blood sugar is the most serious special concern with this medication. If you are diabetic, be sure to discuss this with your prescriber, as a different antipsychotic may be a better choice. Recent studies confirm that although the risk of weight gain and a disturbance of the body’s metabolic system occurs from several different antipsychotics, olanzapine is the most likely to lead to weight gain, although this side effect is linked to the dosage.
Withdrawal symptoms may result from stopping olanzapine. Discontinuation should occur gradually and with your prescriber’s supervision. Support groups, both online and in person, may be helpful when discontinuing these or any psychiatric medications, as the process can be uncomfortable and/or risky in terms of the possibility of the resurgence of symptoms.
In addition, lawsuits were brought against the manufacturer due to the marketing of this medication for off label use with nursing home patients suffering from Alzheimer’s disease. Olanzapine was marketed as effective for dementia despite the lack of evidence supporting this. In fact, Eli Lilly, the drug’s manufacturer did have studies showing a lack of effectiveness for these patients and pled guilty to the charges in this case.