Although fentanyl-induced cough is generally transient and benign, it can give rise to serious problems in patients to whom increasing intracranial, intraocular or intraabdominal pressures may create dangerous situations. This case demonstrates aspiration pneumonia as a complication, exhibiting severe cough induced by intravenous injection of fentanyl.

Porphyrias are inherited metabolic disorders resulting from a specific enzyme defect in the heme biosynthetic pathway. Porphyrias are induced by various precipitants. Clinical features include abdominal pain, neurologic manifestations, autonomic neuropathy, and mental disturbance. Diagnosis may be delayed because of variable symptoms that mimic other diseases and because of the rarity of of porphyrias. Although most patients with known porphyria can complete anesthesia and surgery safely, undiagnosed porphyric patients are in danger of porphyric crisis due to inadvertent exposure to precipitating drugs and environment. We report a case of a patient who experienced delayed emergence with neurological disturbance after general anesthesia, ultimately diagnosed as acute intermittent porphyria.