Guiding treatment in obsessive compulsive disorders by a pharmacogenetic approach

Obsessive-compulsive disorder (OCD) is a common and often enduring neuropsychiatric disorder that results in significant impairments in quality of life. Mostly commonly, its pharmacological management entails a course of a selective serotonin reuptake inhibitors (SSRIs) for ten to twelve weeks, but at higher doses than are typical for treating major depression disorder (MDD). However, the relatively high SSRI doses bring a significant risk for dropout due to side effects in the highly anxious OCD population. We now illustrate through a clinical case study how the use of pharmacogenetics (PGx) in an OCD patient enabled a personalized pharmacological strategy giving better therapeutic response along with lesser risk of untoward side effects. In our case, the patient’s poor clinical responses to initial trials with fluoxetine and escitalopram led us to undertake her pharmacogenetic profiling, which correctly predicted that high dose sertraline would obtain effective management of OCD symptoms. This case report illustrates how PGx assessment can enable physicians to make a more confident and personalized choice of SSRI and dosage, leading to improved patient compliance and a stronger therapeutic response, along with lesser side effects. Pharmacogenetic testing presents an emerging tool for guiding SSRI prescription for OCD, considerably improving the management of these difficult-to-treat patients.