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Risk Exists Between Clozapine Use and Serious Bowel Problems

January 28, 2020

The FDA released a Drug Safety Communication to raise awareness of the risk between clozapine use and serious bowel problems.

Clozapine (Clozaril®) is a medication used to treat schizophrenia. Constipation is a common side effect of clozapine therapy, but in some cases, it can cause serous bowel complications such as complete bowel obstruction, paralytic ileus and intestinal ischemia or infarction. If these serious effects are left untreated, they may lead to hospitalization or even death. The risk is further increased when clozapine is used at higher doses or when clozapine is co-prescribed with medications that have anticholinergic effects or slow GI motility (e.g., antihistamines, antidepressants, opioids).

The FDA is requiring a new warning and updates about this risk to be added to the prescribing information of all clozapine products.

The increased risk of serious bowel problems with clozapine was identified through reports to the FDA MedWatch program and the medical literature. To help the FDA track safety issues with medicines, please report them to to the MedWatch program as recommended in the Indian Health Manual and include “IHS” in the reporter section (section G).

Instructions for reporting can be found online at the NPTC Pharmacovigilance website.