The FDA recently warned of rare, but serious side effects associated with the anti-seizure drug Onfi (clobazam). Onfi is a medication from the benzodiazepine family that is used to treat seizures associated with a severe form of epilepsy. It is manufactured by Lundbeck and has been prescribed to over 31,000 patients in the U.S. since its approval in 2011.
Based on evaluation of its own Adverse Event Reporting System, medical literature, and information from the manufacturer, the FDA has identified 21 cases worldwide involving serious skin reactions. All of the cases resulted in hospitalization, one case lead to blindness, and one case resulted in death. In addition, ‘[f]ive of the six U.S. cases involved children.”
As a result of the findings, the FDA has advised patients to “seek immediate medical treatment and talk to their health care professional if they develop rashes, blistering or peeling of the skin, mouth sores, or hives.” Health care professionals are urged to discontinue the use of Onfi “at the first signs of rash, unless it is clearly not drug-related.” However, patients should not stop taking Onfi without first consulting with their physicians, as stopping the drug suddenly can induce serious withdrawal reactions.
The FDA has also updated the prescription label for Onfi and the patient Medication Guide in order to disseminate detailed information on the risks of serious skin reactions.