Postinjection Delirium/Sedation Syndrome After 31st Long-Acting Olanzapine Depot Injection.

Objective: Long-acting depot preparations of antipsychotics are the mainstay of treatment for patients with schizophrenia who show nonadherence to their medications. Olanzapine pamoate is one of the recently approved long-acting depot psychotropic preparations that have shown its efficacy both in clinical trials and in clinical uses against the illness. However, emerging literature indicates toward a cluster of adverse effects known as postinjection delirium/sedation syndrome (PDSS).

Methods: We here present a case of PDSS in a woman with paranoid schizophrenia. After maintaining well for almost 1½ years, she developed PDSS at her 31st scheduled long-acting olanzapine injection.

Results: Several features of PDSS including its mechanism and course have been discussed.

Conclusions: More research is necessary to understand the syndrome and the association between PDSS and long-acting olanzapine injection. Clinicians should keep in mind that PDSS may worsen compliance in an index patient and affect the course of the illness.