The importance of chirality to antihypertensive drug effects

Abstract

Our objective was to determine the chirality of many popular antihypertensive drugs, that is, whether they contained an asymmetric carbon atom and therefore would exist as more than one enantiomer (isomers that are mirror images of one another, like the right hand to the left hand). After conducting a literature search and contacting several pharmaceutical companies and individual authorities on the subject, we tabulated the chiral identity of 27 antihypertensive drugs. Results indicate that 14 (52%) of the 27 antihypertensive agents studied are marketed as racemic mixtures. Because enantiomers generally have disparate clinical and biologic activities, and because information about the relative efficacy and adverse effects of specific enantiomers is generally lacking in the medical literature, we urge that single enantiomers be used in future clinical trials and pharmacologic studies. Rational therapeutics require the study of the individual components of racemic combinations before such compounds are marketed.