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What is The drug for OPD analgesia is: and explain in detail?
Alfentanil is a potent but sho-acting synthetic opioid analgesic drug, used for anaesthesia in surgery. It is an analogue of fentanyl with around 1/4 to 1/10 the potency of fentanyl and around 1/3 of the duration of action, but with an onset of effects 4x faster than fentanyl.