Haloperidol in the treatment of infantile autism: effects on learning and behavioral symptoms.

In this double-blind, placebo-controlled study the administration of haloperidol resulted in significant decreases in behavioral symptoms and in general clinical improvement in 40 autistic children ages 2.33 to 6.92 years. Haloperidol also produced greater facilitation and retention of discrimination learning in the laboratory. No adverse effects were observed at therapeutic doses, which ranged from 0.5 to 3.0 mg/day or 0.019 to 0.217 mg/kg per day.