Psychopharmacology of impulse-control disorders

Impulse-control disorders are characterized by the failure to resist an impulse or drive to perform an act that may have harmful consequences either to the individual or others. Pathological gambling is the most well recognized and widely studied of the disorders categorized by DSM-IV-TR criteria, in terms of both prevalence and pharmacological treatment. The other disorders categorized by DSM-IV-TR are intermittent explosive disorder, kleptomania, pyromania and trichotillomania. Other less well recognized disorders of impulse control include skin picking, compulsive buying and compulsive computer use. A review of the literature indicates that impulse-control disorders may be relatively common and are likely to be underreported. Individuals diagnosed with an impulse-control disorder are likely to have other other psychiatric co-morbidities, particularly mood, substance use and obsessive-compulsive disorders. A current or lifetime diagnosis of a co-existing psychiatric disorder complicates both the diagnosis and the choice of treatment in an individual with an impulse-control disorder. However, studies published to date have indicated that selective serotonin reuptake inhibitors (SSRIs), atypical antipsychotics, opiate antagonists and mood stabilizers may all have a place in the treatment of these disorders. Very few randomized, controlled studies have been performed, however, particularly in the less well recognized impulse-control disorders, and larger studies are required in these heterogeneous populations to determine the efficacy of these therapies.