[Suspected phenibut poisoning with brainstem involvement]

Phenibut (β-phenyl-γ-aminobutyric acid) is a GABA-B agonist associated with sedation, dependency, and withdrawal. In this case report, a young man was admitted unconscious with partial brainstem areflexia. Based on clinical findings, a container of phenibut found on him, and his later statement of ingestion, phenibut intoxication was suspected, and he was admitted to the ICU. He later developed withdrawal symptoms, treated effectively with baclofen. This highlights phenibut as a potential cause of coma and the role of baclofen in withdrawal treatment.