title: Elevated theophylline blood levels from institution of nifedipine therapy.
mesh_terms: D004347:Drug Interactions; D006801:Humans; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000009:adverse effects*; D013806:Theophylline / Q000097:blood*
chemical_list: D013806:Theophylline; D009543:Nifedipine