No, Salvia divinorum is not the "most potent hallucinogen known to man." Salvinorin A, the active ingredient in S. divinorum, is active orally at over 1mg and its threshold oral doses are around 250-500 micrograms. There are a large number of psychoactives which are more potent than Salvinorin A. LSD, for example, has threshold oral activity at under 50 micrograms and is thus more than an order of magnitude more potent than salvinorin A.

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