Bitolterol mesylate aerosol in adults with steroid-dependent asthma: a comparison with isoproterenol hydrochloride aerosol.
A double-blind randomized study of 29 patients was conducted to evaluate the efficacy, safety, and possible subsensitivity of bitolterol mesylate aerosol and isoproterenol hydrochloride aerosol in the treatment of patients with moderate to severe steroid-dependent asthma. Patients received two sprays, three times a day, of either bitolterol or isoproterenol for 3 months. There were four 8-hour office visits at approximately 30-day intervals to assess pulmonary function. On days when pulmonary functions were evaluated, electrocardiogram and laboratory analysis were performed to help assess safety. Both medications gave bronchodilatation within five minutes. Bitolterol had a maximum effect within 60 minutes while isoproterenol was within 15 minutes. The magnitude of peak effect was consistently greater for bitolterol, but not statistically different from isoproterenol. The mean FEV1 (forced expiratory volume in one second) remained at least 15% or greater above baseline for four to eight hours postmedication for bitolterol on the four monthly pulmonary function test days, compared with one to two hours postmedication for isoproterenol. Both medications were well tolerated, with no significant changes in pulse rate, blood pressure, or respiratory rate. Adverse reactions were mild to moderate in nature and were typical sympathomimetic effects. There were no clinically significant laboratory changes or electrocardiographic findings. During the 3-month study, there was no evidence of subsensitivity. Bitolterol mesylate aerosol was shown to be an effective bronchodilator with a prolonged duration of action in steroid-dependent asthma.
D000293:Adolescent; D000328:Adult; D000336:Aerosols; D000368:Aged; D001249:Asthma / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004983:Ethanolamines / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D006801:Humans; D007545:Isoproterenol / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D013256:Steroids / Q000627:therapeutic use
D000336:Aerosols; D004983:Ethanolamines; D013256:Steroids; C011685:bitolterol; D007545:Isoproterenol