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What is Which of the following drugs is a full agonist at opioid receptors, has excellent oral bioavailability, analgesic equipotency to morphine and a longer durationlof action with milder withdrawal symptoms on abrupt discontinuation? and explain in detail?
(Ref: KDT 6/e p459, 460) Methadone is a long acting opioid agonist that has equal potency to morphine. It can be used orally for opioid replacement and opioid rotation therapy. Due to longer half life, it produces mild withdrawal symptoms.