title: Pulmonary effects of topical timolol.
abstract: Timolol, a beta-adrenergic blocking agent, recently became available for the treatment of glaucoma. We report the occurrence of acute bronchospasm in a previously asymptomatic asthmatic patient following topical use of timolol. Therapy with the drug was discontinued, and four weeks later the patient was challenged with two drops of 0.5% timolol. A 25% decrease in forced expiratory volume at one second (FEV1) was demonstrated at one hour. The fall in FEV1 was even greater (47%) when the patient was rechallenged with four drops. We emphasize the need to avoid topical beta-adrenergic blocking agents in asthmatic patients.
mesh_terms: D000287:Administration, Topical; D000368:Aged; D001249:Asthma / Q000150:complications; D001986:Bronchial Spasm / Q000139:chemically induced*; D006801:Humans; D008297:Male; D009883:Ophthalmic Solutions; D011412:Propanolamines / Q000009:adverse effects*; D012129:Respiratory Function Tests; D013999:Timolol / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D009883:Ophthalmic Solutions; D011412:Propanolamines; D013999:Timolol