J Neuropsychiatry Clin Neurosci 1993; 5:307-315
Copyright © 1993 by American Neuropsychiatric Association
Clinical and neurochemical effects of fenfluramine in children with autism
BL Leventhal, EH Cook Jr, M Morford, AJ Ravitz, W Heller and DX Freedman
Department of Psychiatry, University of Chicago, IL 60637.
Fifteen children with autism were treated with 60 mg d,l-fenfluramine (FEN)
or placebo in a double-blind A-B-A protocol followed immediately by
double-blind placebo-controlled crossover administration of FEN (total
duration 62 weeks). Both biochemical and clinical outcomes were examined.
Biochemically, FEN led to an increase in dihydroxyphenylacetic acid (DOPAC)
and decreases in whole-blood serotonin (5-HT), plasma norepinephrine (NE),
and plasma 3-methoxy-4- hydroxyphenylglycol (MHPG). The decrease in
whole-blood 5-HT was seen only during treatment with FEN. However, NE
levels did not return to baseline as long as 8 weeks after the first FEN
treatment period. Increases in DOPAC were greater during the second FEN
treatment period than the first. Persistent changes in catecholamine
regulation may be related to previously reported long-term effects on
central nervous system 5-HT after FEN. Clinically, FEN led to a modest
decrease in parent, but not teacher, ratings of hyperactivity and to a
small reduction in sensorimotor abnormalities. Abnormal social and
affectual responses also decreased, but this was not directly related to
FEN treatment. Effects on cognition were equivocal. Hyperserotonemic
subjects did not differ from normoserotonemic subjects in clinical
response. Overall, no significant advantage for the use of FEN could be
established.
