Failure of naltrexone hydrochloride to reduce self-injurious and autistic behavior in mentally retarded adults. Double-blind placebo-controlled studies.
BACKGROUND
It is hypothesized that self-injurious behavior (SIB) and symptoms of autism may be due to overactivity in some opioid systems in the brain. We examined the efficacy and safety of naltrexone hydrochloride, an opioid antagonist, in the treatment of SIB and autism in mentally retarded adults.


METHODS
Thirty-three mentally retarded adults with autism and/or SIB participated in double-blind, placebo-controlled crossover studies. Active treatment was first a single 100-mg dose of naltrexone hydrochloride. Subsequently, 19 subjects were treated with 50 mg/d and 14 with 150 mg/d of naltrexone hydrochloride for 4 weeks. The outcome was assessed by means of direct observations (n = 11) and on the basis of scores on a list of target behaviors, the Aberrant Behavior Checklist, and the Clinical Global Impression Scale.


RESULTS
Thirty-two subjects (seven with autism, 16 with autism and SIB, and nine with SIB) completed the trial. Naltrexone treatment failed to have therapeutic effects on SIB and autism. On the contrary, naltrexone increased the incidence of stereotypic behavior on the Aberrant Behavior Checklist, and the care staff evaluated the effect of the 50-mg/d treatment as being significantly worse than that of the placebo treatment as measured by the Clinical Global Impression Scale.


CONCLUSIONS
Our findings suggest that naltrexone has no clinical value for a broad group of mentally retarded subjects with SIB and/or autism.
Willemsen-Swinkels
S H
SH
Department of Child Psychiatry, Rudolf Magnus Institute for Neurosciences, University of Utrecht, The Netherlands.
Buitelaar
J K
JK
Nijhof
G J
GJ
van England
H
H
D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000188:drug therapy* / Q000453:epidemiology / Q000523:psychology; D015897:Comorbidity; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D015994:Incidence; D008607:Intellectual Disability / Q000453:epidemiology / Q000523:psychology*; D008297:Male; D008875:Middle Aged; D009271:Naltrexone / Q000627:therapeutic use*; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D016728:Self-Injurious Behavior / Q000188:drug therapy* / Q000453:epidemiology; D013239:Stereotyped Behavior / Q000187:drug effects; D016896:Treatment Outcome
D010919:Placebos; D009271:Naltrexone