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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Naltrexone is used to maintain abstinence following opioid withdrawal in addicts. It blocks all of the following features of opioid use, except:
assistant
The correct answer is  Ref: Goodman and Gilman 12th/661 *Naltrexone has no action in the absence of agonists but promptly reverses the opioid effects when administered i.v. *It can reverse all effects of opioid like sedation, analgesia, constipation, respiratory depression and Miosis etc but it do not reduce craving.