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What is True statement regarding methadone are all EXCEPT and explain in detail?
Essentials of medical pharmacology, seventh edition, page no 476 Answer is option 4, onset of analgesia is 30-40min after parenteral administration and 1-2 hours after oral administration. Methadone is a long acting u-receptor. It is rapidly absorbed from gastrointestinal tract. Here all statements are true except 4. Ref ; KATZUNG 13TH ED.