IRCT2016062623705N6 IRCT 2016-07-03 Vice Chancellor for Research Affairs, Kermanshah University of Medical Sciences , Kermanshah Univers The effect of augmentation of Gabapentin and Memantine with Selective Serotonin Re uptake Inhibitors (SSRIs) in treatment of patients with Obsessive Compulsive Disorder (OCD). The effect and no effect of augmentation of Gabapentin and Memantine with Selective Serotonin Reuptake Inhibitors (SSRIs) in treatment of patients with Obsessive Compulsive Disorder (OCD). 2016-08-22 anticipated 75 Complete https://irct.ir/trial/20212 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment. N/A Obsessive Compulsive Disorder. Intervention 1: In the experimental group 1, the participant will receive a SSRI drugs with Memantine (SSRI with a dose of 20 mg, Memantine 5 mg) daily. then questionnaire will be redistributed at baseline,4 weeks later, and at the end of the study (8 weeks after the start of the study), and the severity of obsessive-compulsive disorder will be measured. Intervention 2: In the control group, the participant will receive a SSRI drugs include Fluoxetine with placebo(Fluoxetine40 to 60 mg ) daily,then the questionnaire will be re-distributed at the baseline, 4 weeks later, and at the end of the study (8 weeks after the start of the study), and the severity of obsessive-compulsive disorder will be measured. Intervention 3: In the experimental group 2, the participant will receive a SSRI drugs with Gabapentin (SSRI with a dose of 20 mg, Gabapentin150 mg) daily. then questionnaire will be redistributed at baseline,4 weeks later, and at the end of the study (8 weeks after the start of the study), and the severity of obsessive-compulsive disorder will be measured.