Lysergic acid diethylamide, commonly known as LSD, is a potent psychedelic drug that intensifies thoughts, emotions, and sensory perception. Often referred to as acid or lucy, LSD can cause mystical, spiritual, or religious experiences. At higher doses, it primarily induces visual and auditory hallucinations. LSD is not considered addictive, because it does not produce compulsive drug-seeking behavior. Using LSD can lead to adverse psychological reactions, such as anxiety, paranoia, and delusions. Additionally, it may trigger "flashbacks," also known as hallucinogen persisting perception disorder (HPPD), where individuals experience persistent visual distortions after use.
Psychedelics are a subclass of hallucinogenic drugs whose primary effect is to trigger non-ordinary mental states and a perceived "expansion of consciousness". Also referred to as classic hallucinogens or serotonergic hallucinogens, the term psychedelic is sometimes used more broadly to include various types of hallucinogens, such as those which are atypical or adjacent to psychedelia like salvia and MDMA, respectively.
Psilocin, also known as 4-hydroxy-N,N-dimethyltryptamine (4-OH-DMT), is a substituted tryptamine alkaloid and a serotonergic psychedelic. It is present in most psychedelic mushrooms together with its phosphorylated counterpart psilocybin. Psilocin is a Schedule I drug under the Convention on Psychotropic Substances. Acting on the serotonin 5-HT2A receptors, psilocin's psychedelic effects are directly correlated with the drug's occupancy at these receptor sites. The subjective mind-altering effects of psilocin are highly variable and are said to resemble those of lysergic acid diethylamide (LSD) and N,N-dimethyltryptamine (DMT).
2,5-Dimethoxy-4-iodoamphetamine (DOI) is a psychedelic drug of the amphetamine and 4-substituted-2,5-dimethoxyamphetamine (DOx) families.
Amides of lysergic acid are collectively known as lysergamides or ergoamides, and include a number of compounds with potent agonist and/or antagonist activity at various serotonin and dopamine receptors. Lysergamides contain an embedded tryptamine structure, and as a result can produce similar, often psychedelic, effects to those of the true tryptamines.
Methylergometrine, also known as methylergonovine and sold under the brand name Methergine, is a medication of the ergoline and lysergamide groups which is used as an oxytocic in obstetrics and as an antimigraine agent in the treatment of migraine headaches. It reportedly produces psychedelic effects similar to those of lysergic acid diethylamide (LSD) at high doses.
Lisuride, sold under the brand name Dopergin among others, is a monoaminergic medication of the ergoline class which is used in the treatment of Parkinson's disease, migraine, and high prolactin levels. It is taken by mouth.
N-Morpholinyllysergamide, also known as lysergic acid morpholide, is a derivative of ergine (lysergamide). 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.
A serotonin receptor agonist is an agonist of one or more serotonin receptors. They activate serotonin receptors in a manner similar to that of serotonin, a neurotransmitter and hormone and the endogenous ligand of the serotonin receptors.
Ariadne, also known chemically as 4C-D or 4C-DOM, by its developmental code name BL-3912, and by its former tentative brand name Dimoxamine, is a little-known psychoactive drug of the phenethylamine, amphetamine, and phenylisobutylamine families. It is a homologue of the psychedelics 2C-D and DOM.
Lysergic acid 2,4-dimethylazetidide (LA-SS-Az, LSZ) is an analog of LSD developed by the team led by David E. Nichols at Purdue University. It was developed as a rigid analog of LSD with the diethylamide group constrained into an azetidine ring in order to map the binding site at the 5-HT2A receptor. There are three possible stereoisomers around the azetidine ring, with the (S,S)-(+) isomer being the most active, slightly more potent than LSD itself in drug discrimination tests using trained rats.
Methylisopropyllysergamide is an analogue of LSD that was originally discovered by Albert Hofmann at Sandoz during the original structure-activity research into LSD. It has subsequently been investigated in more detail by the team led by David E. Nichols at Purdue University. Methylisopropyllysergamide is a structural isomer of LSD, with the alkyl groups on the amide nitrogen having been subjected to a methylene shuffle. MIPLA and its ethylisopropyl homologue EIPLA are the only simple N,N-dialkyl lysergamides that approach the potency of LSD itself, being around 1/3-1/2 the potency of LSD, while all other dialkyl analogues tested are only around 1/10 as potent as LSD, although some N-monoalkyl lysergamides such as the sec-butyl and t-butyl derivatives were also found to show an activity profile and potency comparable to LSD, and the mono-isopropyl derivative is only slightly weaker than MIPLA. Apart from its lower potency, the hallucinogenic effects of methylisopropyllysergamide are similar to those of LSD itself, and the main use for this drug has been in studies of the binding site at the 5-HT2A receptor through which LSD exerts most of its pharmacological effects.
Lysergic acid 2-butyl amide (2-Butyllysergamide, LSB) is an analogue of LSD originally developed by Richard Pioch at Eli Lilly in the 1950s, but mostly publicised through research conducted by the team led by David E. Nichols at Purdue University. It is a structural isomer of LSD, with the two ethyl groups on the amide nitrogen having been replaced by a single sec-butyl group, joined at the 2-position. It is one of the few lysergamide derivatives to exceed the potency of LSD in animal drug discrimination assays, with the (R) isomer having an ED50 of 33nmol/kg for producing drug-appropriate responding, vs 48nmol/kg for LSD itself. The corresponding (R)-2-pentyl analogue has higher binding affinity for the 5-HT1A and 5-HT2A receptors, but is less potent in producing drug-appropriate responding, suggesting that the butyl compound has a higher efficacy at the receptor target. The drug discrimination assay for LSD in rats involves both 5-HT1A and 5-HT2A mediated components, and while lysergic acid 2-butyl amide is more potent than LSD as a 5-HT1A agonist, it is slightly less potent as a 5-HT2A agonist, and so would probably be slightly less potent than LSD as a hallucinogen in humans. The main use for this drug has been in studies of the binding site at the 5-HT2A receptor through which LSD exerts most of its pharmacological effects, with the stereoselective activity of these unsymmetric monoalkyl lysergamides foreshadowing the subsequent development of compounds such as lysergic acid 2,4-dimethylazetidide (LSZ).
25B-NBOMe is a derivative of the phenethylamine psychedelic 2C-B, discovered in 2004 by Ralf Heim at the Free University of Berlin. It acts as a potent full agonist for the 5HT2A receptor. Duration of effects lasts about 3–10 hours, although the parent compound is rapidly cleared from the blood when used in the radiolabeled form in tracer doses. Recently, Custodio et al. (2019) evaluated the potential involvement of dysregulated dopaminergic system, neuroadaptation, and brain wave changes which may contribute to the rewarding and reinforcing properties of 25B-NBOMe in rodents.
2-Bromo-LSD, also known as BOL-148 or as bromolysergide, is a derivative of lysergic acid invented by Albert Hofmann, as part of the original research from which the closely related compound LSD was also derived. It is a non-hallucinogenic serotonin 5-HT2A receptor partial agonist, as well as acting at other targets, with psychoplastogenic and antidepressant-like effects in animals.
The head-twitch response (HTR), also sometimes known as wet dog shakes (WDS) in rats, is a rapid side-to-side head movement that occurs in mice and rats when the serotonin 5-HT2A receptor is activated. Serotonergic psychedelics like lysergic acid diethylamide (LSD) and psilocybin consistently induce the HTR in rodents. Because of this, the HTR is widely employed in scientific research as an animal behavioral model of hallucinogen effects and in the discovery of new psychedelic drugs.
1-Methylpsilocin (developmental code names CMY, CMY-16) is a tryptamine derivative developed by Sandoz which acts as a selective agonist of the serotonin 5-HT2C receptor (IC50Tooltip half-maximal inhibitory concentration of 12 nM, vs. 633 nM at 5-HT2A), and an inverse agonist at 5-HT2B (Ki of 38 nM). While 1-methylpsilocin does have higher affinity for 5-HT2C than 5-HT2A, it does produce a head-twitch response in mice that is dependent on 5-HT2A, so it is not entirely free of effects on 5-HT2Ain vivo. In contrast to psilocin, 1-methylpsilocin did not activate 5-HT1A receptors in mice.
The 25-NB (25x-NBx) series, or NBOMe series, also known as the N-benzylphenethylamines, is a family of serotonergic psychedelics. They are substituted phenethylamines and were derived from the 2C family. The most commonly encountered NBOMe drugs are 25I-NBOMe, 25B-NBOMe, and 25C-NBOMe.
ETFELA is an analog of lysergic acid diethylamide (LSD) first synthesised by Jason C. Parrish as part of the research team led by David E. Nichols. In studies in vitro, it was found to be slightly more potent than LSD itself.
1V-LSD, sometimes nicknamed Valerie, is a psychotropic substance and a research chemical with psychedelic effects. 1V-LSD is an artificial derivative of natural lysergic acid, which occurs in ergot alkaloids, as well as being an analogue of LSD. 1V-LSD has been sold online until an amendment to the German NpSG was enforced in 2022 which controls 1P-LSD and now 1cP-LSD, 1V-LSD and several other lysergamides.
