Understanding Mescaline: What drug do you get from cactus?

October 9, 2025 •

4 min read

Evidence suggests mescaline, the primary psychoactive alkaloid found in cacti like peyote, has been used in ceremonial contexts for over 5,700 years. This powerful hallucinogen is the answer to the question, "What drug do you get from cactus?", and it originates from several species native to the Americas.

Quick Summary

Mescaline is a hallucinogenic compound derived from specific cacti, notably peyote and San Pedro, with a long history of spiritual and ceremonial use. The potent alkaloid is classified as a controlled substance in many regions but holds cultural significance for Indigenous communities.

Key Points

Mescaline is the Key Drug: The primary psychoactive compound found in certain cacti is the hallucinogenic alkaloid mescaline.
Peyote and San Pedro are the Sources: Mescaline is most famously derived from the peyote (Lophophora williamsii) and San Pedro (Echinopsis pachanoi) cacti.
Deep Cultural Significance: Indigenous peoples in both North and South America have used these mescaline-containing cacti for centuries in religious and healing rituals.
Modulates Serotonin Receptors: Mescaline's hallucinogenic effects are mediated by its agonist activity on the serotonin 5-HT2A receptor in the brain.
Complex Legal Status: Mescaline is a Schedule I controlled substance in the US, with an important legal exemption for the religious use of peyote by members of the Native American Church.
Conservation Concerns for Peyote: The slow growth of the peyote cactus, combined with overharvesting, has led to concerns about its long-term viability in the wild.

Mescaline: The Primary Psychoactive Compound

Mescaline (3,4,5-trimethoxyphenethylamine) is the primary psychoactive alkaloid responsible for the hallucinogenic effects associated with certain cacti. Chemically, it is a substituted phenethylamine and is structurally related to catecholamine neurotransmitters like adrenaline and noradrenaline, though it primarily affects the serotonergic system. The compound was first isolated and identified from the peyote cactus in 1897 by German chemist Arthur Heffter. The effects are similar to other classic psychedelics, including psilocybin and LSD, though mescaline has a lower potency.

The Two Main Cactus Sources

While mescaline can be synthesized in a laboratory, it occurs naturally in several types of cacti, with the most well-known being peyote and San Pedro. The concentration of mescaline can vary significantly depending on the species, growing conditions, and specific part of the plant.

Peyote (Lophophora williamsii)

Appearance: A small, spineless cactus with disc-shaped "buttons" that appear above the soil.
Habitat: Native to northern Mexico and the southwestern United States.
Harvesting: The buttons are cut off and can be chewed fresh, dried, or steeped in water to make a tea.
Potency: Mescaline content can range from 0.01% to 5.5% of the dried weight.
Traditional Use: Used for millennia by Indigenous peoples in religious and healing ceremonies.

San Pedro Cactus (Echinopsis pachanoi)

Appearance: A fast-growing columnar cactus native to the Andes Mountains.
Habitat: Found throughout the Andes region of Peru and Ecuador.
Harvesting: Prepared by boiling pieces of the cactus to create a psychoactive decoction.
Potency: Mescaline concentrations can range from 0.23% to 4.7% of the dried weight.
Traditional Use: Has a history of use spanning over 3,000 years in shamanic rituals in South America.

Pharmacology, Effects, and Associated Risks

Mescaline's psychoactive effects are primarily mediated by its action as an agonist at the serotonin 5-HT2A receptor in the brain. This leads to a range of subjective and physiological effects. The user's experience is heavily influenced by their mindset and the environment (referred to as "set and setting").

Effects

Psychological: Hallucinations (often visual and geometric), altered sense of time and space, introspection, euphoria, and synesthesia. Some users also report insightful spiritual experiences.
Physiological: Initial and intense nausea, vomiting, increased heart rate, elevated blood pressure, pupil dilation, and increased body temperature. These physical symptoms often precede the psychedelic experience.

Risks

While overdose leading to death is extremely rare with mescaline, misuse can cause serious psychological distress. Psychological dependence is possible, and some individuals may experience anxiety, paranoia, or depression during a "bad trip". The illegal status also poses significant legal risks for unauthorized users.

Comparing Peyote and San Pedro


Feature	Peyote (Lophophora williamsii)	San Pedro (Echinopsis pachanoi)
Appearance	Small, spineless, rounded cactus with "buttons".	Large, columnar, fast-growing cactus.
Growth Rate	Extremely slow, often taking many years to reach maturity.	Relatively fast-growing compared to peyote.
Mescaline Potency	Varies widely, generally higher concentration in dried material.	Varies widely, mescaline concentrated in the green skin.
Cultural Origin	North America (Mexico, SW US) with long history of Indigenous use.	South America (Andean region), used in traditional medicine for millennia.
Conservation	Endangered due to overharvesting and slow growth.	Not endangered, and is widely cultivated.
Legal Status (USA)	Schedule I controlled substance; religious exemption for NAC members.	Generally legal to grow as an ornamental plant; extracts are illegal.

Legal Landscape and Conservation Concerns

In the United States, mescaline is classified as a Schedule I controlled substance, indicating a high potential for abuse and no accepted medical use. The peyote cactus is also controlled, but federal law provides an exemption for the sacramental use of peyote by members of the Native American Church (NAC). This exemption recognizes the profound spiritual importance of the cactus to Indigenous traditions, which use it in healing and religious ceremonies.

However, the slow growth rate of peyote and increasing demand have raised significant conservation concerns. Conservationists and Indigenous leaders are worried about overharvesting, habitat destruction, and the long-term sustainability of wild peyote populations. Conversely, the fast-growing San Pedro cactus is not endangered and is legally sold as an ornamental plant in many places, though preparing it for consumption is illegal.

Conclusion

Mescaline is the psychoactive drug derived from cacti like the slow-growing peyote and the faster-growing San Pedro. This naturally occurring alkaloid has a rich history in Indigenous cultures, who have used it for thousands of years in spiritual and healing ceremonies. While its legal status is complex and varies by region, its cultural and historical significance is undeniable. Research into the therapeutic potential of mescaline and other psychedelics has seen a revival, though its Schedule I status severely limits modern study. The future of mescaline from cactus sources will hinge on navigating legal frameworks, respecting Indigenous practices, and addressing critical conservation issues for the vulnerable peyote cactus.

Frequently Asked Questions

Mescaline is a naturally occurring psychedelic alkaloid derived from certain cacti, notably peyote and San Pedro. It is a hallucinogen that can induce altered states of consciousness, vivid visual patterns, and spiritual experiences.

Mescaline and peyote are classified as Schedule I controlled substances in the United States, making recreational use illegal. However, federal law provides a specific exemption for members of the Native American Church (NAC) to use peyote in their religious ceremonies.

Peyote is a small, spineless, and very slow-growing cactus native to North America, primarily used by Indigenous communities like the NAC. The San Pedro is a larger, fast-growing columnar cactus native to the Andes region of South America. Both contain mescaline, but their growth rates, native regions, and cultural contexts differ significantly.

The most common methods involve chewing the fresh or dried cactus buttons (peyote) or brewing a tea or decoction from pieces of the cactus (peyote or San Pedro). Synthetic mescaline also exists and can be taken in pill form.

Effects can include visual and auditory hallucinations, altered perception of time and space, and profound introspection. Physical effects often include nausea, vomiting, increased heart rate, and elevated blood pressure, particularly in the initial phase.

While physical dependence on mescaline is not considered a high risk, psychological dependence can occur with habitual use. The drug's hallucinogenic nature also carries the risk of a distressing or psychologically challenging experience, commonly referred to as a "bad trip".

The peyote cactus is slow-growing and its natural habitat has been threatened by both overharvesting for religious and recreational use and habitat loss. This has raised significant concerns about its long-term survival and availability for traditional Indigenous practices.