Isoergine, also known as isolysergic acid amide (iso-LSA or iso-LA-819), isolysergamide, or erginine, is a serotonergic psychedelic of the ergoline and lysergamide families related to ergine (lysergic acid amide; LSA) and lysergic acid diethylamide (LSD). It is the epimer of ergine inverted at the 8 position. Along with ergine and other ergolines, isoergine occurs naturally in morning glories. It is thought to be primarily responsible for the hallucinogenic effects of morning glory seeds.
Use and effects Isoergine occurs naturally in morning glory species, including Ipomoea tricolor (tlitliltzin), Ipomoea corymbosa (ololiuhqui), and Argyreia nervosa (Hawaiian baby woodrose). It has been found to constitute 8 to 35% of total alkaloid content relative to 5 to 58% for ergine.
Albert Hofmann, the discoverer of LSD's psychedelic effects, tried 2mg isoergine orally and experienced feelings of unreality, detachment from the outside world, feelings of mental emptiness, tiredness, and apathy, though no specific sensory distortions were mentioned. He described its effects as similar to those of ergine, which he had tested at doses of up to 2mg. Subsequently Heim and colleagues assessed ergine at higher doses of 3 to 6mg orally and observed toxic-like effects, while isoergine at 2 to 5mg orally produced notable hallucinogenic effects. The psychedelic effects of isoergine observed in this study included some euphoria, synaesthesia, and altered time perception. However, although hallucinogenic, isoergine's effects have been described as not LSD-like. The presence of hallucinogenic effects of isoergine has been described as quite unusual for an isolysergamide derivative.
It is thought that ergine and isoergine together may account for most or all of the effects of morning glory seeds, with ergine producing intoxication, sedation, and autonomic side effects and isoergine producing hallucinogenic effects. Conversely, other notable constituents, including elymoclavine, lysergol, and chanoclavine, produced no psychoactive or hallucinogenic effects in humans. Ergometrine, which is a minor constituent representing up to 8% of total alkaloids, is known to produce psychedelic effects only in higher amounts (2–10mg) than those in typical doses of morning glory seeds and hence is thought to not contribute to the effects of the seeds either. Moreover, ergometrine is present in Ipomoea tricolor and Argyreia nervosa but not in Ipomoea corymbosa. Isoergine being responsible for the hallucinogenic effects of morning glory seeds is also supported by animal studies.
According to Alexander Shulgin in his 1997 book TiHKAL (Tryptamines I Have Known and Loved) however, both ergine and isoergine are "probably correctly dismissed" as not contributing to the effects of morning glory seeds. https://www.erowid.org/library/books_online/tihkal/tihkal26.shtml "LA-111, Ergine, d-Lysergamide. This is an active compound and has been established as a major component in morning glory seeds. It was assayed for human activity, by Albert Hofmann in self-trials back in 1947, well before this was known to be a natural compound. An i.m. administration of a 500 microgram dose led to a tired, dreamy state with an inability to maintain clear thoughts. [...] The epimer, inverted at C-8, is isoergine or d-isolysergamide, and is also a component of morning glory seeds. Hofmann tried a 2 milligram dose of this amide, and as with ergine, he experienced nothing but tiredness, apathy, and a feeling of emptiness. Both compounds are probably correctly dismissed as not being a contributor to the action of these seeds. It is important to note that ergine, as well as lysergic acid itself, is listed as a Schedule III drug in the Controlled Substances Act, as a depressant. This is, in all probability, a stratagem to control them as logical precursors to LSD. [...] Although there are many other chemical treasures in the ergot fungal world, I would like to wrap this commentary up with a return to the topic of morning glory seeds. Four additional alkaloids of the ergot world must be acknowledged as being potentially participating factors in the MGS story. [...] These structures in effect define absolute obscurity, and most probably do not contribute to the morning glory intoxication state. But the others, some present is sizable amounts, may someday help explain why the pharmacology of these seeds is so different than that of the major isolates, the ergines." The poorly-stable lysergic acid hydroxyethylamides (LSHs) might alternatively be involved in the psychedelic effects of morning glory seeds per Shulgin.
Interactions
The interactions of isoergine and of morning glory seeds have been discussed.
Pharmacology Pharmacodynamics Isoergine shows affinity for serotonin receptors labeled with serotonin or LSD in rat brain membranes. It has about 10- to 25-fold lower affinity for these receptors than serotonin or LSD and has the same affinity as ergine and iso-LSD ( = 100–200nM for isoergine, 200nM for ergine and iso-LSD, and 8–10nM for LSD). No other receptor interaction data are available for isoergine as of 2020. However, computer-predicted receptor affinities are available for ergine/isoergine (stereochemistry not taken into account). The drug is said to have about 4.3% of LSD's antiserotonergic potency in vitro. It is 5- to 33-fold less potent than LSD in producing behavioral changes in the conditioned avoidance test in rodents.
Pharmacokinetics The pharmacokinetics of isoergine in rodents have been studied. Isoergine is much less lipophilic than LSD, with log P values of 0.95 and 2.95, respectively. This might influence its pharmacological properties, for instance reducing its blood–brain barrier permeability. However, isoergine showed a similar ratio of brain-to-plasma levels as LSD in rodents.
Chemistry Derivatives Derivatives of isoergine include isolysergic acid diethylamide (iso-LSD), isolysergic acid hydroxyethylamide (iso-LSH), and ergometrinine (isoergometrine; isolysergic acid propanolamide), among others. With the apparent exception of isoergine, isolysergamides, such as iso-LSD, have been found to be inactive as psychedelics in humans.
History Isoergine was first identified by Sidney Smith and Geoffrey Timmis in 1936 via hydrolysis of ergot alkaloids. This followed the identification of ergine in the same way in 1932. Isoergine was first synthesized by Albert Hofmann and colleagues by 1949. Subsequently, it was isolated by Hofmann and colleagues in morning glory seeds in 1960. The psychoactive effects of isoergine were first described by Hofmann in 1963. Heim and colleagues more clearly substantiated the hallucinogenic effects of isoergine and its role in producing the psychedelic effects of morning glory seeds in 1968.
Society and culture Legal status Canada Isoergine is not a controlled substance in Canada as of 2025.
United States Ergine is not an explicitly controlled substance in the United States. However, it could be considered a controlled substance under the Federal Analogue Act if intended for human consumption.
See also Ergine (lysergic acid amide; LSA; lysergamide) Aztec use of entheogens § Ololiuqui and Tlitliltzin Morning glory § Chemistry and ethnobotany List of entheogens List of psychoactive plants
References
External links Isoergine - Isomer Design LSD-25 (Discusses Isoergine) - TiHKAL - Erowid LSD-25 (Discusses Isoergine) - TiHKAL - Isomer Design