Introduction: Many of the pharmacologically active substances, used in various pharmaceutical products, are chiral organic compounds and can exist in one of several optically active isomer forms. Usually one of the enantiomers is pharmacologically active, while the inactive enantiomer can show unwanted side effects, and in some cases, even antagonistic or toxic effects can be observed. Therefore, a need for resolution of the enantiomers and for enantiomeric purity control arises.
Aim: To overview the bases of drug stereochemistry with regard to pharmacokinetic and pharmacodynamic parameters of chiral pharmaceuticals, used as single enantiomers or racemates, as well as the analytical methods for isolation and separation of the different enantiomer isoforms.
Materials and Methods: systematic review of web databases (PubMed, ScienceDirect and Google Scholar) on the problem.
Results: The different enantiomers and diastereomers of chiral pharmaceutical substances can vary in the terms of their absorption and bioavailability, protein binding and distribution throughout the organism, metabolism pathways and excretion, as well as the extent of the pharmacological activity, therapeutic effect and toxicity. Since obtaining pure drug enantiomers through enantioselective synthesis is not always practical, separation of the racemic mixtures can be achieved with chromatographic and electroseparation techniques, which prove to be more cost-effective.
Conclusions: A better understanding of the pharmacological differences between drug enantiomer forms is required. Furthermore, administration of single enantiomer products rather than racemates or vice versa can lead to treatment options that are more successful. The required resolution of drug enantiomers can be achieved to a desirable extent using modern analytical methods.
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