Perampanel is a novel antiepileptic drug that has been used as an adjunctive treatment for focal-onset seizures. No reports to date have documented respiratory suppression as a side effect of perampanel in adults. Herein, we report a 51-year-old man with focal epilepsy presented with type 2 respiratory failure after accidently consuming of 66 mg of perampanel. Clinicians should consider the possibility of respiratory compromise whenever a high dose of perampanel needs to be administered to patients.