N-Morpholinyllysergamide (developmental code name LSM-775), also known as lysergic acid morpholide, is a derivative of ergine (lysergamide).[1] It is less potent than lysergic acid diethylamide (LSD) but is reported to have some LSD-like effects at doses ranging from 75 to 700 micrograms and a shorter duration. LSM-775 may only produce weak or threshold psychedelic effects in humans.[2]
The drug is a potent full agonist of the serotonin 5-HT1A receptor and a potent partial agonist of the serotonin 5-HT2A, 5-HT2B, and 5-HT2C receptors. It does not produce the head-twitch response, a behavioral proxy of psychedelic effects, in rodents. However, LSM-775 can robustly increase head twitches if it is coadministered with the serotonin 5-HT1A receptor antagonist WAY-100635. These findings indicate that serotonin 5-HT1A receptor activation suppresses the psychedelic-like effects of LSM-775.
There are claimed to be fewer signs of cardiovascular stimulation and peripheral toxicity with LSM-775 compared to LSD.[3]