Fluoxetine treatment of severe self-injury in young adults with mental retardation.

Dysfunction of the serotonergic system has been implicated in the development and maintenance of self-injury in some persons with mental retardation. Several preliminary reports have suggested that fluoxetine, a drug that blocks the reuptake of serotonin, may decrease self-injury in these individuals. Of the 44 cases of self-injury treated with fluoxetine and previously reported in the literature, 42 demonstrated a beneficial response to the drug. We report four additional cases of adults with mental retardation whose self-injury was treated with fluoxetine. Each of these individuals benefited from fluoxetine to some extent, with average decreases in self-injury ranging from 20% to 88% when compared with baseline levels. These findings, combined with those from previously published case studies, emphasize the need for well-controlled studies to more adequately assess the effects of fluoxetine on self-injury.