We evaluated the use of topically administered betaxolol, a cardioselective beta-adrenergic blocking agent, in 11 patients (eight women and three men, 40 to 81 years old) who had asthma and severe glaucoma with increased intraocular pressure despite maximally tolerated medical therapy. In each of these patients, timolol was either contraindicated or had previously led to development of pulmonary symptoms or complications. Before betaxolol, mean forced expiratory volumes in one second were 66% in the men and 80% in the women of reported normal values in age- and height-matched groups. Betaxolol was then topically administered twice daily. All patients continued to administer betaxolol without exacerbation of pulmonary symptoms and without deterioration in measured pulmonary function tests. Betaxolol further reduced intraocular pressure by a mean of 18% (4 mm Hg) when added to the patients' otherwise maximal regimen.