Enkephalinase inhibitors attenuate naloxone-precipitated withdrawal syndrome

Enkephalinase inhibitors phosphoramidon, thiorphan or phelorphan suppressed naloxone-precipitated withdrawal symptoms in acute and chronic morphine dependent mice and rats. It is suggested that decreased biotransformation of the endogenous opioid peptides might compensate the relative shortage of exogenous opiates during withdrawal in opiate dependent subjects and could be a new and promising way to attenuate the severity of abstinential syndrome.