Carteolol hydrochloride: controlled evaluations of its ocular hypotensive efficacy relative to its vehicle, and, in combination with pilocarpine, relative to timolol.

Carteolol is a noncardioselective beta-adrenoceptor antagonist with intrinsic sympathomimetic activity. In the two studies presented in this report, we sought (a) to evaluate the absolute efficacy of carteolol (i.e., vs. its vehicle) over an extended period and (b) to evaluate the utility of carteolol versus that of timolol when used concomitantly with pilocarpine. Study 1 was a double-masked, randomized, 6-week evaluation conducted in 64 patients of 1% carteolol HCl, 2% carteolol HCl, and its vehicle given twice daily in both eyes. From an unmedicated baseline intraocular pressure (IOP) of 23-25 mm Hg, mean reductions in the carteolol treatment groups ranged from 5.8 to 6.6 mm Hg (23-26% reduction). Mean reductions in heart rate were six to seven beats/min, two beats/min, and one beat/min in the 1% carteolol, 2% carteolol, and vehicle groups, respectively. Study 2 was a double-masked, randomized, 12-week evaluation of 1% carteolol HCl, 2% carteolol HCl, and 0.5% timolol in combination with pilocarpine, either 2% or 4%, in 67 patients. From an unmedicated baseline IOP of 24-29 mm Hg, mean reductions from this unmedicated baseline with combination beta-adrenoceptor antagonist/pilocarpine treatment ranged from 6 to 10 mm Hg in all groups (24-40%). Mean decreases in heart rate ranged from one to six beats/min, with no meaningful differences among the treatment groups. Based on the efficacy of twice-daily carteolol in reducing IOP by approximately 25%, as well as its efficacy when used concomitantly with pilocarpine, we suggest that clinicians may find carteolol a useful addition to their pharmacopeia in the treatment of elevated IOP.