A treatable language disorder: pharmacological treatment of pervasive developmental disorder.

Results of treatment of four patients are described. All of the patients had pervasive developmental disorder (PDD), a tic disorder, and a characteristic pattern of speech and language impairment. The patients were treated with haloperidol for their tic disorders, and concomitant with the reduction of the frequency and severity of tics was marked improvement in language. The patients averaged 3 months of language gain for each week of speech therapy directly after the initiation of haloperidol treatment for tics. Progress in speech and language therapy was extremely slow during the years prior to treatment with haloperidol. To the authors' knowledge, no language disorder has been described in the literature which shows such a predictable and marked response to pharmacological treatment. The authors hypothesize that tic disorders in individuals with PDD may be a marker for a more positive response to dopamine antagonists like haloperidol.