Using Drug Augmentation to Treat Obsessive Compulsive Disorder Patients Who Did Not Respond to Previous Treatment

Pharmacological Augmentation Strategies for Obsessive Compulsive Disorder Patients Non-respondent to First Line Medication Treatment: a Double Blind Placebo Controlled Study

This will be a controlled, randomized, double-blind and double-dummy study on the treatment augmentation strategy for obsessive compulsive disorder patients non-respondent to first line pharmacological treatment. The investigators will compare: fluoxetine maintenance at maximum dosage for additional 12 weeks; the association of fluoxetine with quetiapine; and the association of fluoxetine with clomipramine.

Arm 1: SSRI (Fluoxetine 40mg* once a day) + Clomipramine 75mg* once a day.

Arm 2: SSRI (Fluoxetine 40mg* once a day) + Quetiapine 200mg* once a day.

Arm 3: SSRI (Fluoxetine 80mg* once a day) + Placebo once a day.

*or maximum tolerated dose

We hypothesize that quetiapine and clomipramine will be effective augmentation strategies for resistant OCD patients in comparison to placebo.

Inclusion Criteria:

1. OCD diagnosis
2. YBOCS score ≥ 16 (for patients with both obsessions and compulsions) or ≥ 10 (for patients with only obsessions or compulsions)
3. Previously signed informed consent to participate in this clinical trial

Exclusion Criteria:

1. Patients with clinical or neurological diseases that may be worsen by the medications included in treatment protocol
2. Current substance dependence or abuse
3. Current psychotic symptoms
4. Current suicide risk
5. Current pregnancy or intention to get pregnant before the end of the treatment protocol