To describe the initial results of implementing pharmacogenomics testing in a community-based psychiatry practice and potential impacts on medication management.

Retrospective chart review of prospectively maintained medical records of all adult patients with pharmacogenomics results from 9/01/2017 to 6/30/2019 under the care of psychiatrist and clinical pharmacist.

A total of 51 patients met inclusion criteria. A total of 7 pharmacokinetic genes and, due to changes in the test report over time, a range of 6-10 pharmacodynamic genes relevant to psychotropic medications were evaluated per patient. Every patient had genetic variations, with an average of 6.1 per patient (range 3-9; SD= 1.5). Patients were taking an average of 3.6 (range 1-8; SD=1.7) psychiatric medications at the time of the genetic test, to treat an average of 5 psychiatric conditions (range 1-9; SD=2.2). An average of 1.2 (range 0-4; SD=1.0) gene-drug interactions were uncovered per patient. Following review by psychiatrist and pharmacist, medication adjustments resulted in patients remaining on an average of 3.6 psychiatric medications, but decreasing the average number of gene-drug interactions per patient to 0.8 (range 0-3, SD=0.8).

The large number of genetic variations observed per patient is consistent with previous findings 1-2. The decrease in number of gene-drug interactions following testing demonstrates the practical utility of pharmacogenomics information to guide medication therapy. This study did not examine outcomes such as improvement in psychiatric condition or reduction in medication adverse effects; however, these endpoints have been evaluated in other trials 3-4.

Pharmacogenomics testing presents an opportunity for a personalized medicine approach in a community-based psychiatry practice.