Despite the substantial clinical improvements provided by the pharmacologic and cognitive-behavior therapies of OCD, it has been estimated that 40%–60% of patients still remains refractory to conventional treatment.

Medication augmentation can be an effective and well-tolerated short-term treatment strategy for non-responders to first-line pharmacotherapy of obsessive-compulsive disorders.

To investigate the efficacy of paliperidone as augmenting agent in the treatment of resistant OCD patient.

In the present case, we present a 6 months follow-up of an obsessive-compulsive patient treated with paliperidone ER and fluvoxamine. Paliperidone ER was started at 6mg/day and increased up to a maximum of 12mg/day. The clinical symptoms were measured by Y-BOCS and efficacy measures with CGI and PSP scale scores.

We found that obsessive-compulsive symptoms improved after 4weeks. Patient showed a significant improvement over the 6 months follow-up for Yale-Brown Obsessive Compulsive Scale total score at week 24 as compared with baseline (from a score of 34 to a score of 12). A significant improvement in the mean PSP scale score was also seen and “much improved” on the CGI score from baseline to end point. A mean bodyweight change of ≤2kg over the 24-week study period observed, but there were no clinically meaningful changes in glucose, insulin and blood lipid levels. There was no adverse event reported after the augmentation with paliperidone.

Adding paliperidone to SSRIs could be a valid strategy for treatment-resistant OCD patients and additional efficacy studies and randomized, double-blind studies are needed.