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Serotonin-1D Hypothesis of Obsessive-Compulsive Disorder: An Update

J Clin Psychiatry 2004;65(suppl 14):18-21

Support for the serotonin-1D (5-HT1D) hypothesis of obsessive-compulsive disorder (OCD) and related conditions comes from a variety of sources. Some pharmacologic challenges with the 5-HT1D agonist sumatriptan, and case reports in which prolonged administration of 5-HT1D agonists was associated with a therapeutic effect, suggest that 5-HT1D may play a role in obsessive-compulsive symptoms. Genetic studies have also found that polymorphism of the 5-HT1D gene may be preferentially transmitted to those patients with OCD. However, taking into account that OCD is a heterogeneous syndrome, the 5-HT1D hypothesis requires further investigation in order to disentangle the role of the 5-HT1D receptor in this common and often severe disorder.