spec sheet10 rows
LSM-775 (lysergic acid morpholide) is a lysergamide in which the diethylamide of LSD is replaced by a morpholine ring. In vitro screening characterizes it as a nonselective agonist at serotonin 5-HT1A and 5-HT2A receptors, and it is metabolized primarily by CYP1A2 and CYP3A4 through N-dealkylation and hydroxylation. In mice, LSM-775 fails to elicit the head-twitch response, a proxy for 5-HT2A-mediated hallucinogenic activity, unless the 5-HT1A receptor is first blocked; this suggests that concurrent 5-HT1A activation dampens its psychedelic signature. These findings are consistent with anecdotal reports that LSM-775 produces only weak, short-lived LSD-like effects in humans.
- Milder and shorter than LSD
- Lighter psychedelic character
- Lysergamide headspace at lower intensity
- Nonselective 5-HT1A agonism masks its head-twitch response
- Autonomic and physical effects
- Vasoconstriction
- Nausea possible
Mechanism
LSM-775 works as an at the receptor, the receptor behind the psychedelic state, but the morpholide amide reduces its potency relative to LSD. Reports and older studies describe a shorter, lighter experience, sometimes with more autonomic or physical effects for its psychedelic strength. Its full receptor profile is only loosely characterized.
receptor fingerprint
receptoragonist
receptoragonist
Safetyrisks and cautions, not medical advice
LSM-775 is weaker than LSD but still an active lysergamide with little formal safety data. Avoid with a personal or family history of psychosis or bipolar disorder, and never combine lysergamides with MAOIs or strongly serotonergic drugs (serotonin toxicity), or with lithium or tramadol (seizure reports). Not medical advice.
Subjective profileweighing the evidence above
Poorly characterized and not obviously worth the trouble. It reads as a weaker, shorter LSD carrying more autonomic and physical load per unit of headspace, with little formal safety data and the usual lysergamide rules about MAOIs, lithium and tramadol still in force. Mostly interesting for what its missing head-twitch response says about 5-HT1A.
Resources
This entry is here for reference.
Research
- 1.Return of the lysergamides. Part IV: Analytical and pharmacological characterization of lysergic acid morpholide (LSM-775)
- 2.In vitro metabolic fate of nine LSD-based new psychoactive substances and their analytical detectability in different urinary screening procedures
2 listed here; entry last updated August 2026
Reviews
My notesprivate to this device
FAQ
How strong is LSM-775?
It is generally reported as noticeably weaker and shorter than LSD, with a lighter overall character.
Is it a prodrug of LSD?
No; it is its own lysergamide, distinct from the 1-acyl LSD prodrugs.
Is much known about it?
Only a little; it is a rare, historical compound with limited data. This is not medical advice.
Limitations of the evidence
- Poorly characterized
Adverse effects
- Autonomic and physical effects
- Vasoconstriction
- Nausea possible