Translation of science to clinical practice in psychiatry has begun only recently. Limitations have included lack of clear relationship between the serum concentrations of many neuropsychiatric drugs and efficacy, a relatively wide therapeutic window for many of these medications, lack of pharmacogenomic guidelines, and a limited number of trials investigating pharmacogenomic testing in ways that can be translated to the clinical practice. In addition, many psychiatric and neurological diseases are thought to be polygenetic and multifactorial in etiology, with multiple medication classes commonly used to manage symptoms. This further complicates our understanding of how and when to use testing in clinical environments.
