[beta-Adrenergic receptor blockers--a group of chiral drugs: different effects of each enantiomer].

The present review of beta-adrenergic receptor blockers deals with different pharmacodynamic, pharmacokinetic and toxicological effects of individual enantiomers in the group of arylaminoethanols and aryloxyaminopropanols. From the viewpoint of beta-adrenolytic activity, (-)-enantiomers in both groups are several times more effective and in many beta-blockers both enantiomers show different therapeutic indications. The absolute configuration in the sense of Cahn-Ingold-Prelog system exists in (-)-enantiomers in the group of arylaminoethanols (R) and in the group of aryloxyaminopropanols (S). Of the beta-blockers hitherto used in therapeutic practice, pure enantiomers are (S)-(-)-penbutolol, (S)-(-)-timolol, and (S)-(-)-levobunolol. The hitherto research in this field, however, does not unambiguously answer, as the experience with labetalol, sotalol, and timolol shows, the question of the advantages of therapeutic use of pure enantiomeric forms.