PLASMA BETA-ENDORPHIN LEVELS, NALTREXONE, AND HALOPERIDOL IN AUTISTIC-CHILDREN

Plasma beta-endorphin levels were measured in 13 autistic children, ag ed 3.67 to 11.67 years at the end of treatment (naltrexone, haloperido l, pimozide, or placebo) and in 5 of the 13 children also at baseline. Baseline plasma beta-endorphin levels were lower than those reported in the literature. There was a strong correlation between plasma beta- endorphin levels and severity of sterotypies in all children. Naltrexo ne did not seem to have a specific effect on plasma beta-endorphin lev els; short-term haloperidol treatment was associated with an increase, whereas long-term haloperidol treatment seemed to have a depressive e ffect on plasma beta-endorphin levels, which rose after withdrawal of haloperidol.