Stereochemistry in Drug Action.
The importance of stereochemistry in drug action is gaining greater attention in medical practice, and a basic knowledge of the subject will be necessary for clinicians to make informed decisions regarding the use of single-enantiomer drugs. Many of the drugs currently used in psychiatric practice are mixtures of enantiomers. For some therapeutics, single-enantiomer formulations can provide greater selectivities for their biological targets, improved therapeutic indices, and/or better pharmacokinetics than a mixture of enantiomers. This article reviews the nomenclature for describing stereochemistry and enantiomers, emphasizes the potential biological and pharmacologic differences between the 2 enantiomers of a drug, and highlights the clinical experience with single enantiomers of the selective serotonin reuptake inhibitors fluoxetine and citalopram. In some cases, both a mixture of enantiomers and a single-enantiomer formulation of a drug will be available simultaneously. In these cases, familiarity with stereochemistry and its pharmacologic implications will aid the practicing physician to provide optimal pharmacotherapy to his or her patients.
McConathy
Jonathan
J
Laboratory of Neuropsychopharmacology, Department of Psychiatry & Behavioral Sciences, Emory University School of Medicine, Atlanta, Ga.
Owens
Michael J.
MJ