Alkaloid Groups - A Brief OverviewAlkaloids are a group of chemical compounds which are characterized by carbon rings that usually contain nitrogen and by the fact that they are usually basic on the PH scale.  Alkaloids are produced by a large variety of organisms, including plants, animals, bacteria and fungi. Alkaloids are particularly important to the study of entheogens because many of them have pharmacological effects and may be used as medicines, recreational drugs or spiritual catalysts.  In fact, in much of the history of screening of plants for psychoactive and medicinal compounds, any species found to contain no alkaloids has been disregarded for the most part. Although in recent years it has been discovered that many other chemical classes have great therapeutic value, alkaloids are nevertheless some of the most powerful chemical agents that we are presently aware of.

Human beings have been using alkaloid-containing plants for hundreds of years, and indeed, you will find that most of the entheogens that have been examined and discussed by ethnobotanists contain some kind of alkaloids.  In 1804, the German chemist Friedrich Serturner isolated the first known alkaloid, morphine, from opium.  Since that time, more than 12,000 alkaloids have been identified.  The following alkaloid groups are those that are the most relevant to the study of entheogens, and hopefully this discussion will help to clarify the descriptions of individual entheogens found elsewhere on this site (Voogelbreinder 2009).

Indole Alkaloids

The indole alkaloid group contains some of the most important and useful compounds in the field of entheology.  The effects  of indole alkaloids can be described as psychedelic, with secondary effects ranging from mental excitation and physical sedation to physical excitation and sexual arousal.  In general, these alkaloids effect the serotonin neurotransmitter system, but also effect the norepinephrine system, the dopamine system, and others.

The indole alkaloid group includes the tryptamines, which include DMT, 5-methoxy-DMT and bufotenine. These are found in an incredible variety of plants as well as in some amphibians.  The indole alkaloid group also includes psilocybin and psilocin, which are found in a number of species of fungi. Interestingly enough, psilocin is formed from DMT through oxidation, and is then phosphorylated into psilocybin (Voogelbreinder 2009).

Furthermore, the ergoline and clavine type alkaloids, such as LSA, which are found in the ergot fungi as well as in certain species of morning glory, are part of the indole alkaloid group.  The ergoline indole alkaloids are also the source of LSD.  The indole alkaloid group also contains the B-carbolines, which include harmine and harmaline, powerful MAO inhibitors, as well as substances such as yohimbine, a powerful aphrodisiac found in yohimbe bark, mitragynine, the active component found in kratom, and ibogaine, the powerful addiction-fighting component of iboga.  Even the neurotransmitter serotonin is a product of a simple indole alkaloid.

The first indole alkaloid to be isolated was strychnine in 1818 by Pierre Joseph Pelletier and Joseph Bienaime Caventou. Indole alkaloids act on the central and peripheral nervous systems. Due to the structural similarities of many indole alkaloids with serotonin, many of them interact with 5-HT serotonin receptors as agonists.  This is thought to be the main cause of the visionary effects of many indole-alkaloid-containing entheogens. However, some indole alkaloids interact with other types of receptors.  Mytragynine, found in kratom, is an agonist of the u-opioid receptor, and the harmal alkaloids are antagonists of the GABAa receptor (Voogelbreinder 2009).

It is clear from the above information that indole alkaloids are some of the most important to the study of entheogens, if not the most important.  From psilocybin mushrooms to LSD to ayahuasca, many of the most powerful and accessible entheogens on the planet owe their effects directly to indole alkaloids. People have been using plants containing indole alkaloids as entheogens and medicines for thousands of years.  These compounds have been influencing and shaping religion and society for longer than anyone can remember, and they will no doubt continue to do so in the future! (Voogelbreinder 2009)

Isoquinoline Alkaloids

Isoquinoline alkaloids are often found in cacti, and display a wide variety of pharmacological effects.  Some, such as vasicinone, are also found in Peganum harmala.  Many, including morphine and codeine, are found in the poppy family, Papaveraceae.  Isoqinoline alkaloids have been found to have anticholinergic and antihistamine properties.  Some also inhibit the acetylcholinesterase enzyme in the brain (Voogelbreinder 2009).

Isoxazole Alkaloids

The isoxazole alkaloids are a small group of chemicals found in some fungi, specifically Amanita muscaria, the fly agaric mushroom.  The isoxazole alkaloids contained in this mushroom are ibotenic acid and muscimol.  These are GABA-agonists in the central nervous system, and produce a strange dissociative state in individuals who consume plants containing these alkaloids (Voogelbreinder 2009).

Phenethylamine Alkaloids

The phenethylamine alkaloid group contains compounds that are primarily stimulating, some of which also have psychedelic effects.  They are found primarily in the families Cactaceae (cacti) and Leguminosae (legumes, including Acacia), but are also found in substances such as chocolate.  Phenethylamine alkaloids usually effect the norepinephrine and dopamine neurotransmitter systems, although mescaline is a phenethylamine which also effects serotonin receptors, and which is found in cacti such as peyote, peruvian torch and San Pedro.  This group also contains stimulants such as ephedrine, cathinone and amphetamine (Shulgin et al. 1990).

Many naturally occurring phenethylamine alkaloids are not orally active, and are presumed to be active with MAO-B inhibition (Shulgin et al. 1990).  Phenethylamine alkaloid use generates free radicals in the body.  In order to prevent potential oxidative damage and reduce negative side-effects, antioxidants should be taken alongside substances containing phenethylamine (Leibovitz 1993).

It has been found that individuals with ADHD and clinical depression have abnormally low levels of endogenous phenethylamine, while individuals suffering from schizophrenia have abnormally high concentrations. Many increasingly popular synthetic psychedelic substances, including MDMA and 2C-B are synthesized from natural phenethylamine alkaloids (Shulgin et al. 1990).

Purine Alkaloids

The purine alkaloids are stimulants, most familiarly found in tea, coffee, cola nuts, some species of Ilex (from which Yerba Mate is made), and guarana.  The best known purine alkaloid is caffeine.  Theobromine, found in chocolate, is another well known stimulating purine alkaloid.  Simple purines like guanine and adenosine are the basis of nucleic acids such as DNA and RNA.  Stimulating purine alkaloids produce their effects primarily by inhibiting adenosine receptor activity (Voogelbreinder 2009).

Pyrrolidine and Piperidine Alkaloids

Pyrrolidine and piperidine alkaloids are mostly central nervous system stimulants which affect the acetylcholine neurotransmitter system.  Many display high toxicity.  Pyrrolidine alkaloids include nicotine, from tobacco and arecoline from Areca catechu (betel nut), among others.  These are sometimes used as anti-convulsants.

Piperidine alkaloids such as piperine and piperidine are mostly found in species of the genus Piper, including Piper methysticum (kava kava).  Most piperidine alkaloids are CNS-depressants (Voogelbreinder 2009).

Quinolizidine Alkaloids

The quinolizidine alkaloids are extremely toxic and are mostly found in members of the Leguminosae family.  They are potentially psychoactive in humans, but these effects are always accompanied by dangerous side effects. Many quinolizidine alkaloids show an affinity for nicotinic acetylcholine receptors, while some others show an affinity for the muscarinic acetylcholine receptors.  The quinolizidine alkaloid cystine, found in the mescal bean, Sophora secundiflora, was used as a visionary element by indigenous tribes in the Southwest (Seigler 2011).

Tropane Alkaloids

Tropane alkaloids are found primarily in the plants of the Solanaceae family, which includes the genera Datura, Brugmansia and Atropa.  These alkaloids are quite toxic, but can be used in small doses as medicines to combat motion sickness and to cause dilation of the pupils.  Certain tropane alkaloids are known to create a powerful delirious visionary state that is accompanied by memory loss and motor-control loss.  Negative side-effects may include blindness and temporary insanity, while larger doses may lead to death through respiratory paralysis.  Tropane alkaloids are very difficult to work with, and in the past have been favored by witches and sorcerers.  Tropane alkaloids effect dopamine and norepinephrine systems in the brain.  The most common tropane alkaloids found in entheogens are atropine, hyoscine and hyoscyamine (Voogelbreinder 2009).

Cocaine, derived from Erythroxylum coca, is also a tropane alkaloid, and is a stimulant as well as a euphoriant and local anesthetic.  Cocaine does not bring with it any of the delirious visionary effects that many other tropane alkaloids do (Voogelbreinder 2009).


Leibovitz, B. “Phenethylamines, Free Radicals, and Antioxidants.” Newsletter of the Multidisciplinary Association for Psychedelic Studies 4, no. 1 (1993).

Seigler, D.S. “Pyrrolizidine, Quinolizine, and Indolizidine Alkaloids.”, n.d.

Shulgin, A., A. Shulgin, and D.E. Nichols. PIHKAL: A Chemical Love Story. Berkeley, CA: Transform Press, 1990.

Voogelbreinder, Snu. The Garden of Eden: The Shamanic Use of Psychoactive Flora and Fauna and the Study of Consciousness. Snu Voogelbreinder, 2009.