Pharmacogenetics in Psychiatry: Precision medicine or ‘mystic, magic, and mysterious’?

Prescribers and patients are frequently facing the challenge that treatment standards established at a population level might not be beneficial at the individual level. As a result, lengthy trials are often required before the optimum psychiatric medication treatment, single or in combination, is found. The underlying reasons for this large inter-individual variability treatment outcomes are not fully understood. Important factors that influence drug dose, response and side effects include age, gender, patient compliance, clinical symptoms, co-morbidities, lifestyle, ancestry and genetic factors. In this context, first strategies using pharmacogenetic (PGx) information bear the promise to optimize medication treatment in clinical practice. State-of-the-art summaries of key concepts and strategies of psychiatric PGx need to consider: 1) Reviews of the evidence, clinical utility and studies including randomized clinical trials of distinct gene-drug pairs; 2) Discussion of current expert recommendations (e.g., Clinical Pharmacogenomics Implementation Consortium); 3) How PGx information can be best used in clinical practice, in particular to avoid pseudo-resistance for antidepressants 3) Highlighting ongoing implementation efforts and 5) providing practical support for psychiatrists and pharmacologists.