A Study on the Effectiveness of Fluoxetine on Different Clinical
Subtypes of Obsessive-Compulsive Disorder
GOREISHIZADEH MA, M D: Professor of Psychiatry
FARNAM AR, M D: Assistant Professor of Psychiatry (corresponding author)
Department of Psychiatry, Tabriz University of Medical Sciences
The clinical presentation of obsessive - compulsive disorder Background and Objectives:
(OCD) is highly heterogeneous. Fluoxetine has been known as an effective drug in the
treatment of OCD, but there is no convincing information about the effect of the agent on the
subtypes of the illness. This study was conducted to investigate the effectiveness of fluoxetine
in treating three subtypes of OCD (washing, obsessive thoughts, and checking).
Materials and Methods: One hundred OCD patients referred to Razi hospital and two
private clinics in Tabriz, were selected randomly. They were examined by DSM-IV-TR based
interview. Physical and substance related disorders were excluded. They were assigned to
three groups : washing , obsessive thoughts and checking. All groups completed the Yale –
Brown scale before and two months after receiving fluoxetine with average doses between
40-80 mg /day. Two scores (before and after treatment) were compared and analyzed with
statistical paired t – test.
Results: The results showed that all subjects (regardless of their subtypes) significantly
responded to fluoxetine (p < 0.001). Washer subjects and the patients with obsessive thoughts
showed better response to the drug (p-values were 0.000 and 0.001, respectively).
Conclusion: There was a significant difference between checkers and the other groups of
OCD patients in response to fluoxetine therapy and the checker group showed no significant
response. This finding can help physicians in treatment planning of OCD patients.
Keywords: Fluoxetine, Obsessive - compulsive disorder subtypes, Treatment response