oh ok. Hey at least this wasn't a useless post =)

Fentanyl is a powerful opioid analgesic with a potency approximately 81 times that of morphine. Fentanyl has an LD50 of 3.1 milligrams per kilogram in rats and 0.03 milligrams per kilogram in monkeys. The LD50 in humans, by intravenous injection in an opiate-naive individual (without tolerance), is ...

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