Which of the following drugs does not activate opioid receptors, has been proposed as a drug in the management of opioid addiction and with just a single dose blocks the action of injected heroin for up to 48 hours?
(Ref: KDT 6/e p437) Naltrexone is a long acting, orally effective opioid antagonist that can be used as the maintenance treatment of opioid addicts. It is also used to decrease the craving for alcohol.