title: Beta blockers and verapamil: a cautionary tale.
mesh_terms: D000328:Adult; D001262:Atenolol / Q000009:adverse effects*; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D006327:Heart Block / Q000139:chemically induced*; D006801:Humans; D008297:Male; D014700:Verapamil / Q000009:adverse effects*
chemical_list: D001262:Atenolol; D014700:Verapamil