title: Increased clearance of phenytoin as the presenting feature of infectious mononucleosis.
abstract: A 19-year-old man with posttraumatic seizures under good control with phenytoin, 500 mg/day, presented with three seizures. His blood level of phenytoin, previously in a therapeutic range, was 4.2 microgram/ml. No systemic or laboratory evidence of infectious mononucleosis was found. Ten days later, the blood picture became compatible with infectious mononucleosis, at which time his phenytoin clearance returned to normal.
mesh_terms: D000328:Adult; D006801:Humans; D007244:Infectious Mononucleosis / Q000097:blood*; D008297:Male; D010672:Phenytoin / Q000097:blood* / Q000627:therapeutic use; D012640:Seizures / Q000188:drug therapy
chemical_list: D010672:Phenytoin