Psychedelics differ in their chemical structures, mechanisms of action, and resulting effects on users. Factors such as origin (natural or synthetic), duration of action, potency, and subjective experiences can vary significantly between substances. Some of the most well-known psychedelics include:

1. Lysergic acid diethylamide (LSD): A potent psychedelic, LSD was first synthesized by Albert Hofmann in 1938. Its effects include visual and auditory hallucinations, time distortion, and altered perceptions. Research on LSD has increased in recent years, with studies examining its potential for treating mental health conditions like depression and anxiety.^{1 2}
2. Psilocybin: Found in "magic mushrooms," psilocybin is another popular psychedelic. Its effects are similar to LSD but usually have a shorter duration. Recent studies have shown potential benefits for treating depression, anxiety, and addiction.^{3 4}
3. Dimethyltryptamine (DMT): DMT is a naturally occurring psychedelic compound found in many plants and animals. Its effects are intense and short-lived, often described as a "breakthrough" experience involving vivid visuals and perceived contact with other entities. DMT is also the main psychoactive ingredient in ayahuasca, a traditional South American brew used for spiritual and healing purposes. Research on DMT and ayahuasca has suggested potential therapeutic applications in treating addiction, depression, and PTSD.^{5 6}
4. Mescaline: Mescaline is a naturally occurring psychedelic alkaloid found in several cactus species, most notably the peyote (Lophophora williamsii) and San Pedro (Echinopsis pachanoi) cacti. Mescaline produces visual and auditory hallucinations, emotional shifts, and altered perceptions of reality. There has been limited research on mescaline due to legal restrictions, but some studies suggest it may have potential therapeutic uses, particularly in the context of indigenous spiritual practices.⁷
5. 3,4-Methylenedioxymethamphetamine (MDMA): Although not a classic psychedelic, MDMA is often grouped with them due to its empathogenic effects, which can involve profound emotional experiences and increased feelings of empathy and connection. MDMA has been extensively researched for its potential as a treatment for post-traumatic stress disorder (PTSD) in combination with psychotherapy.^{8 9} Its effects differ from classic psychedelics in that it primarily increases the release of serotonin, dopamine, and norepinephrine, leading to mood elevation and increased sociability.
6. Ibogaine: Derived from the root bark of the African shrub Tabernanthe iboga, ibogaine is a powerful psychedelic known for its intense, long-lasting effects, and potential for treating opioid addiction. Research on ibogaine has shown promise in reducing withdrawal symptoms and drug cravings in people with substance use disorders.^{10 11} However, concerns about ibogaine's safety, especially regarding its potential for cardiac toxicity, have limited its widespread use and research.
7. 2C-B, 2C-E, and other 2C-x compounds: These are a family of synthetic phenethylamine psychedelics developed by chemist Alexander Shulgin. They vary in potency and effects, which can include visual and auditory hallucinations, synesthesia, and altered perception of time and space. Research on these compounds is limited due to legal restrictions and their relatively recent emergence.

This list is by no means exhaustive, as there are many other psychedelic compounds, both naturally occurring and synthetic, with varying effects and potential therapeutic applications. Some other examples include:

1. Salvinorin A: Found in the Salvia divinorum plant, salvinorin A is a potent and selective kappa-opioid receptor agonist that produces intense, short-lived dissociative and hallucinogenic effects. Research on salvinorin A is limited, but it has been suggested that it might have potential for treating addiction and mood disorders.¹²
2. 5-MeO-DMT: A close relative of DMT, 5-MeO-DMT is a powerful naturally occurring psychedelic with intense and short-lived effects. While research is still in its early stages, preliminary studies suggest that it may have potential for treating depression and anxiety.¹³
3. Ayahuasca: As mentioned earlier, ayahuasca is a traditional South American brew containing DMT and other compounds that act as monoamine oxidase inhibitors (MAOIs) to make DMT orally active. Research on ayahuasca has focused on its potential therapeutic applications for mental health disorders like depression, anxiety, and PTSD.^{5 6} There is also interest in the potential benefits of the traditional ceremonial context in which ayahuasca is often consumed, as it may facilitate healing and personal growth through its unique set and setting.
4. AL-LAD, ETH-LAD, and other LSD analogs: These are synthetic compounds that are chemically similar to LSD, but with some differences in their effects and duration. They were also explored by chemist Alexander Shulgin and others. Research on these substances is scarce due to their relatively recent emergence and legal restrictions.
5. DOI, DOB, DOC, and other DOx compounds: These are a family of synthetic amphetamine-derived psychedelics that have a longer duration of action compared to classic psychedelics like LSD and psilocybin. Research on these compounds is limited, but they have been used in some experimental studies to understand the neurobiological mechanisms of hallucinations and other psychedelic effects.¹⁴

Finally, another psychedelic which is also considered a dissociative anesthetic is ketamine. While ketamine does not act on serotonergic pathways, the way most other psychedelics do, it still results in similar psychedelic experiences as others. Ketamine is especially helpful for those suffering from significant anxiety or PTSD, as the dissociative nature of the compound is “gentler” for the user.¹⁵

Using psychedelics requires caution due to their unpredictable effects and varying legal statuses. As interest in their therapeutic potential grows, continued rigorous research is crucial to ensure the safety and effectiveness of potential treatments.

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References

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Cover photo by Pawel Czerwinski on Unsplash