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Olanzapine Pamoate (Zyprexa Relprevv) Safety - FDA Concludes Investigation of 2 Unexplained Deaths - Updated

March 24, 2015

In June 2013, FDA notified the public of 2 deaths that occurred in patients who had recently received olanzapine pamoate (Zyprexa Relprevv). The deaths occurred 3 to 4 days after the patients received appropriate dosing of the medication by intramuscular injection.  Tests showed both patients had very high concentrations of olanzapine in the blood stream.  At the time, the deaths were unexplained, and FDA began conducting an investigation into possible causes.

FDA has finished their investigation into these deaths and found the results inconclusive. The deaths may have been caused by rapid delayed entry of olanzapine into the bloodstream, or the increased drug concentrations may have occurred post-mortem. Based on FDA’s review of the information, FDA is not recommending changes to the product labeling for Zyprexa Relprevv.

The Zyprexa Relprevv Risk Evaluation and Mitigation Strategy (REMS) requires continuous monitoring of patients for at least 3 hours after olanzapine pamoate injection. The medication must be administered in a facility that is registered under the REMS program.  The olanzapine pamoate package insert warns that post-injection delirium sedation syndrome (PDSS) may occur when olanzapine is absorbed into the bloodstream too rapidly. Symptoms of PDSS include delirium, sedation, and possible coma. Other symptoms associated with high blood levels of olanzapine include cardiopulmonary arrest and cardiac arrhythmias. Cases of PDSS have been reported with olanzapine pamoate in clinical trials; however, the reported cases occurred within 3 hours of administration and were not fatal.

Follow the instructions for administration and monitoring outlined in the REMS and in the product labeling. Patients are instructed to direct any questions or concerns regarding olanzapine pamoate to their health care providers. Encourage patients to speak with their health care provider before stopping therapy with Zyprexa Relprevv. Report adverse events to the FDA MedWatch Program online ( or by phone (1-800-332-1088).

Additional information is available at the following links:

March 24, 2015; June 19, 2013; University of Utah, Drug Information Service. Copyright 2015, Drug Information Service, University of Utah, Salt Lake City, UT.