What Pharmacogenetic Panels Can — and Cannot — Tell Us About Mental Health Medications

Selecting the most effective medication for a mental health condition is a complex process that often involves trial and error. One tool that has gained attention in recent years is pharmacogenetic testing—a method that analyzes an individual’s genetic makeup to help guide treatment decisions. These tests offer valuable insights, but it’s important to understand both their potential and limitations.

Understanding Pharmacogenetic Panels

Pharmacogenetic panels assess multiple genes involved in how the body metabolizes certain medications, especially those used in psychiatric care. These tests provide insight into whether someone may metabolize a drug too quickly, too slowly, or within the expected range. This information can support healthcare providers in selecting medications or adjusting doses to better align with a patient’s biology.

In this way, pharmacogenetic testing can function similarly to checking for drug interactions before prescribing—offering guidance that may improve treatment decisions but not supplying a complete clinical picture (Hicks et al., 2015).

Limitations of Pharmacogenetic Testing

While informative, genetic data is only one part of the broader picture of medication response. Factors such as age, sex, diet, stress, concurrent medical conditions, and the complex interactions among genes all influence how an individual responds to a particular drug.

In fact, many of the genetic variants these panels evaluate may have limited clinical impact for most individuals, particularly in terms of treatment efficacy and side effect risk (Bousman & Hopwood, 2016).

Ongoing clinical monitoring is essential. Providers must assess how a patient is actually responding to treatment—both in terms of symptom relief and side effects—and make necessary adjustments. In some cases, non-genetic factors such as inflammation or metabolic status may be more relevant to treatment outcomes (Bradley et al., 2018).

Implications for Patients and Providers

Pharmacogenetic panels can be useful tools in the decision-making process, but they are not stand-alone solutions. Clinical experience, patient-reported outcomes, and professional judgment remain central to effective psychiatric care.

In certain situations, healthcare providers may also use therapeutic drug monitoring—measuring drug concentrations in the blood—to ensure dosing is appropriate and effective (Thase et al., 2019).

Ultimately, while pharmacogenetic testing can offer helpful insights, it reveals only one aspect of an individual’s overall health. These panels can inform prescribing decisions, but the most important guide remains the patient’s lived experience: how they feel, function, and respond to treatment over time.

If you're considering whether pharmacogenetic testing could be beneficial for you, the best first step is to speak with your healthcare provider.

References

• Bradley, P., Shiekh, M., Mehra, V., et al. (2018). Improved efficacy with targeted pharmacogenetic-guided treatment of patients with depression and anxiety: A randomized clinical trial demonstrating clinical utility. Journal of Psychiatric Research, 96, 100–107. https://doi.org/10.1016/j.jpsychires.2017.09.021

• Bousman, C. A., & Hopwood, M. (2016). Commercial pharmacogenetic-based decision-support tools in psychiatry. The Lancet Psychiatry, 3(11), 993–995. https://doi.org/10.1016/S2215-0366(16)30225-6

• Hicks, J. K., Bishop, J. R., Sangkuhl, K., et al. (2015). Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines for CYP2D6 and CYP2C19 genotypes and dosing of selective serotonin reuptake inhibitors. Clinical Pharmacology & Therapeutics, 98(2), 127–134. https://doi.org/10.1002/cpt.92

• Thase, M. E., Smith, E., Friedman, E., et al. (2019). Clinical utility of combinatorial pharmacogenomic testing in major depressive disorder: A Canadian patient- and rater-blinded, randomized, controlled trial. PLoS One, 14(5), e0213998. https://doi.org/10.1371/journal.pone.0213998