Pharmacogenetic testing in psychiatry: not (quite) ready for primetime.

To the extent that genetic factors are associated with the efficacy, tolerability, and safety of different drugs, pharmacogenetic tests may be used to personalize medication treatments for an individual. Pharmacogenetic tests, such as GeneSight Psychotropic and the Genecept Assay, are being marketed directly to patients and prescribers despite a relative lack of evidence to support their clinical validity or utility. Pharmacogenetic testing is potentially useful in certain clinical situations, but its usefulness will depend on the knowledge base of the prescriber to be able to interpret the findings for a particular patient. Proposed guidelines on laboratory developed tests will likely encourage, if not require, evidence for the clinical validity and utility of pharmacogenetic tests before they are approved for marketing.