Patients who suffer of obsessive-compulsive disorder (OCD) experience obsessive thoughts and/or urges to engage in compulsive behaviours. the condition causes severe discomfort and, in many cases, leads to serious impairment in social and work-related functioning.

Although antipsychotic monotherapy has been associated with ineffectiveness and even increase of psychotic symptoms (especially in psychotic patients), antipsychotics as adjuvant to antidepressant medication have proven to be effective in several case series and pilot clinical trials.

The objective of this case was to evaluate the effectiveness of clomipramine-quetiapine combination in OCD refractory to serotonin selective reuptake inhibitors treatment patient.

23 years unemployed male was diagnosed with OCD after 1 year from onset and received 3 trials with serotonin selective reuptake inhibitors at therapeutical doses, without any improvement and even more with worsening of affective associated symptoms. We managed this case by using a tricyclic antidepressant (clomipramine up to 100 mg/day) with an atypical antipsychotic (quetiapine up to 200 mg/day). We employed the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), Obsessive-Compulsive Checklist (OCC) and Hamilton Depression rating Scale (HDRS) at baseline, weekly for the first 2 months and monthly after (follow up 2 years).

Patient achieved a very fast and sustained improvement both in obsessive-compulsive and affective symptoms, which provided a very good social and work rehabilitation.

Clomipramine-quetiapine combination may be a benefit for OCD refractory to serotonin selective reuptake inhibitors and a safe strategy.