A Comparative Study of Aripiprazole, Olanzapine, and L-Methylfolate Augmentation in Treatment Resistant Obsessive-Compulsive Disorder.

About half of the patients with Obsessive-compulsive disorder (OCD) do not respond to serotonin reuptake inhibitors (SRIs) or have a partial improvement in their symptoms. This study aimed to compare the efficiency and safety of aripiprazole, olanzapine, and L-methyl folate in patients with resistant OCD. The study consisted of an open-label prospective phase of 12-weeks to ascertain resistance to SRIs and a second 6-week open-label addition phase for non or, partial responders of the first phase. One-hundred-fifteen patients entered the 16-week open-label phase. Fifty patients (43.47%) responded to the SRIs monotherapy, two patients developed adverse effects and another three were lost to the follow up. Sixty patients (52.2%) were considered treatment-resistant and entered the 6-week open-label aripiprazole, olanzapine, or L-methyl folate addition phase; Patients showed a significant improvement over 6-week study period in olanzapine and aripiprazole group as measured by YBOCS total score (p < 0.001) while there was no change in the L-methyl folate group at the end as compared with baseline (p = 0.150). Clinical Global Impression-Severity decreased from 4.90 to 2.90 in olanzapine and aripiprazole group at the end of 6 weeks while there was no change in the L-methyl folate group. The CGI-I was significant in the olanzapine and aripiprazole group (p < 0.001) while it was insignificant in the L-methyl folate group (p = 0.088). Augmentation of SRIs with olanzapine or aripiprazole could be a promising option for resistant OCD. L-methyl folate though shown to be effective in resistant depression was not effective in treatment resistant OCD.