2806 Baclofen toxicity causing coma associated with burst suppression pattern on EEG: a case report and review of the literature

Baclofen is a GABA-B receptor agonist typically prescribed as a muscle relaxant for alleviation of skeletal muscle spasticity, but it is also used for a variety of other purposes including as a drug of abuse and off-label in alcohol use disorder.¹ Baclofen overdose can lead to respiratory depression, cardiac conduction abnormalities, flaccid paralysis, seizures and coma with absent brain stem reflexes mimicking brain death. Baclofen toxicity can influence electroencephalogram (EEG) findings causing a range of abnormalities including generalised slowing, triphasic waves, generalised periodic sharp waves, rhythmic high-amplitude delta waves and non-convulsive status epilepticus.²

We report a case of a 36-year-old male patient presenting with a seizure, respiratory depression and coma following an intentional baclofen and sertraline overdose whose EEG demonstrated a burst suppression pattern; a rarely reported feature of severe baclofen toxicity. The patient went on to make a full recovery, with resolution of the EEG abnormalities with supportive treatment. This article will demonstrate the variety of EEG abnormalities that can occur with baclofen overdose and the importance of applying the history of drug toxicity when interpreting an abnormal EEG. The case highlights that fortunately, even in the presence of severe toxicity and subsequent development of a burst suppression pattern on EEG, patients will likely go on to make a full neurological recovery with supportive care alone.