Statistically, haloperidol was significantly superior to placebo in reducing behavioral symptoms. In a discrimination learning paradigm, autistic children receiving haloperidol learned the discrimination while those on placebo did not. Discrimination attained on haloperidol was retained when the children were switched to placebo. (Author)

The double-blind and placebo controlled study with 45 autistic children (ages 2-7) found that the drug, haloperidol, showed powerful therapeutic effects in reducing behavioral symptoms when administered for 4 weeks at doses raging from 0.25 to 4.0 milligrams/day. Learning effects were not found. (Author/DB)