Reduction of elevated CSF beta-endorphin by fenfluramine in infantile autism

Pediatr Neurol. 1987 Mar-Apr;3(2):83-6. doi: 10.1016/0887-8994(87)90032-4.


Fenfluramine therapy has been reported to improve behavior in infantile autism and has been associated with a decrease in abnormally increased blood serotonin content. The primary central effect has not been proved to be serotonergic. Beta-endorphin is involved in the anorexic effect of fenfluramine and may play a role in autism. Nine children with infantile autism were treated with fenfluramine in double-blind, placebo-crossover design. Transient anorexia was the only adverse effect. Autistic behavior was reported to improve in three patients, but objective psychometric tests were unchanged. Beta-endorphin-like immunoreactivity was determined in lumbar cerebrospinal fluid of patients during and before or after treatment with fenfluramine and then was compared to normal controls. Beta-endorphin was elevated significantly in the baseline autistic group (p less than .005) and was reduced toward control values during fenfluramine treatment. The results are consistent with a role for beta-endorphin in infantile autism and in the mechanism of fenfluramine treatment.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Autistic Disorder / cerebrospinal fluid
  • Autistic Disorder / drug therapy*
  • Child
  • Clinical Trials as Topic
  • Double-Blind Method
  • Female
  • Fenfluramine / adverse effects
  • Fenfluramine / therapeutic use*
  • Humans
  • Male
  • beta-Endorphin / cerebrospinal fluid*


  • Fenfluramine
  • beta-Endorphin