Effects of the R(+)- and S(-)-isomers of beta-adrenoceptor blockers with intrinsic sympathomimetic activity, befunolol and carteolol, on rabbit intraocular pressure.

Effects of the R(+)- and S(-)-isomers of befunolol and carteolol, beta-adrenoceptors with intrinsic sympathomimetic activity, on the rabbit intraocular pressure were tested. The intraocular pressure was decreased by instillation of the R(+)- and S(-)-isomers of befunolol (0.1 and 0.3%) and of carteolol (1.0%) to the eye and attained the minimum level at 60 min. However, 0.3% of the R(+)- and S(-)-isomers of carteolol did not influence the pressure. The corresponding time courses for the intraocular pressure for the R(+)- and S(-)-isomers did not differ, suggesting that in the treatment of glaucoma, the therapeutic advantage of the R(+)-isomers of befunolol and carteolol may be similar to the S(-)-isomers.