Comparison of tetrahydrocannabinol and synhexyl in man

TLDR

A synthetic isomer of THC, considered identical to the most active natural form, was compared with the semisynthetic THC‑like compound synhexyl. Sixteen volunteers received THC (341–946 µg/kg, median 581 µg/kg) and thirteen received synhexyl (633–2,666 µg/kg, median 1,370 µg/kg). Both drugs produced similar psychotomimetic syndromes, but synhexyl had a slower onset and was about one‑third as potent; compared to LSD, they induced prominent sedation, longer‑lasting euphoria, more pronounced dreamlike sequences, and distinct physiological and biochemical effects lacking sympathomimetic activity.

Abstract

A synthetic isomer of tetrahydrocannabinol (1‐Δ'‐3,4‐transtetrahydrocannabinol), believed to be identical to the most active naturally occurring THC, was compared with a semisynthetic THC‐like compound, synhexyl. Sixteen volunteer subiects received THC in doses ranging from 341 to 946 p.g per kilo gram (median 581). Thirteen subjects received synhexyl in doses ranging from 633 to 2,666 µg per kilogram (median 1,370). Clinical syndromes tram the 2 drugs were similar, although synhexyl was slower in onset and only about one third as potent. The clinical effects resembled those of psychotomimetics such as LSD, at least at the higher doses. These drugs differed from LSD in the following respects: sedation was prominent; euphoria was langer lasting; dreamlike sequences more pronounced; and physiological and biochemical effects were somewhat different, especially in the absence of sympathomimetic effects.