A new FDA warning is being added to prescribing information for the anti-seizure drugs levetiracetam and clobazam because the agency found they can cause a rare but serious hypersensitivity: drug reaction with eosinophilia and systemic symptoms (DRESS). Diagnosis of DRESS can be difficult because symptoms vary and may be confused with other reactions. DRESS may start as a rash and can include fever and swollen lymph nodes or injury to the liver, kidneys, lungs, heart, or pancreas. Undiagnosed and untreated, DRESS can quickly lead to internal organ injury or death. The FDA identified 32 serious cases associated with levetiracetam through March 2023, including 2 deaths, and 10 serious cases associated with clobazam.
Make the connection: DRESS can develop 2 to 8 weeks after starting treatment with the drugs, the agency noted, so patients might not associate an acute rash or fever with the initiation of their anti-seizure prescriptions. While rare, DRESS is serious enough to warrant a second look at the patient’s prescription regimens.