Placebo-controlled acute dosage naltrexone study in young autistic children
16 October 1995
In a double-blind, placebo-controlled crossover trial 23 autistic children were treated with a single 40-mg dose of the opiate antagonist naltrexone. Drug effects were monitored by detailed playroom observations, actometers, and parents' checklist ratings (Aberrant Behavior Checklist, social items and target behaviors). Naltrexone treatment failed to produce significant changes in social behavior, but it did reduce irritability and target scores on behavior checklists. The playroom data indicated that naltrexone significantly affected indices of activity and attention.
Conclusions and implications: Combining ultralow doses of micro- or delta-receptor antagonists with spinal morphine augmented the acute analgesic effects, inhibited the induction of chronic tolerance and reversed established tolerance. The remarkably similar effects of micro- and delta-opioid receptor antagonists on morphine analgesia and tolerance are interpreted in terms of blockade of the latent excitatory effects of the agonist that limit expression of its full activity.
Keywords: Ethology, beta-endorphin, cortisol, attention, social behavior, locomotor activity