Successful Phenobarbital Desensitization After DRESS Reaction in the Management of Refractory Status Epilepticus

Drug reaction with eosinophilia and systemic symptoms (DRESS) is associated with antiepileptic drug use and is a rare but life-threatening side effect. We present a case of phenobarbital-induced DRESS in a patient who subsequently required phenobarbital and was successfully desensitized.

A 5-year-old male presented with medically refractory status epilepticus (SE). He had been trialed on several antiepileptic medications without achieving burst suppression. Burst suppression was achieved with a pentobarbital infusion, and thus, phenobarbital was initiated as the pentobarbital was weaned. After five days of phenobarbital, the patient developed signs and symptoms concerning for DRESS; a punch biopsy confirmed the drug reaction. Two months later, he again developed SE unresponsive to antiepileptic infusions. Burst suppression was achieved with pentobarbital, and it was decided to transition the patient to phenobarbital. Due to concerns of phenobarbital-induced DRESS, the patient underwent a phenobarbital desensitization consisting of 6 doses sequentially administered in 10-fold increasing concentrations before achieving therapeutic dosing. Three days later, the patient achieved therapeutic phenobarbital levels, was weaned off of pentobarbital, and remained seizure-free without recurrence of DRESS.

Graded desensitization may be an option to minimize recurrence of DRESS in patients where avoidance of the offending agent is not possible.