ETH-LAD, 6-ethyl-6-nor-lysergic acid diethylamide is an analogue of LSD. It's human psychopharmacology was first described by Alexander Shulgin in the book TiHKAL. ETH-LAD is a psychedelic drug similar to LSD, and is slightly more potent than LSD itself, with an active dose reported at between 20 and 150 micrograms. ETH-LAD has subtly different effects to LSD, described as less demanding.
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^Hoffman AJ, Nichols DE (September 1985). "Synthesis and LSD-like discriminative stimulus properties in a series of N(6)-alkyl norlysergic acid N,N-diethylamide derivatives". Journal of Medicinal Chemistry28 (9): 1252–5. doi:10.1021/jm00147a022. PMID4032428.