TYPM does not encourage any illegal activities or the use or abuse of psychoactive plant medicine or psychedelics. Even within the confines of the law, they are not appropriate or beneficial for everyone.
Plant medicines, and psychedelics are not “magical cures”. They are powerful tools, when used properly with respect, clear intentions, in a safe & supportive environment can catalyze personal growth and healing.  They are not without serious risks.
In order to minimize harm and increase therapeutic potential, it is imperative to do your own research, prepare, and integrate your experience.
The material on this website is offered for informational use only, and is not intended for use in diagnosing or prescribing treatment for any disease or condition. 



San Pedro (Huachuma / Wachuma, Giganton, aguacolla), a member of the Echinopsis pachanoi species, is a cactus native to South America.  San Pedro can induce feelings of empathy, introspection, ego loss, euphoria, as well as visions. 

San Pedro is a widely grown ornamentally in many areas.  Traditionally, San Pedro is consumed for spiritual/religious purposes and is typically prepared by a curandero (a healer), who facilitates the healing done by the plant.  In Andean traditional medicine, San Pedro is most often used to diagnose disease, whereby the healer ingests it to be able to see its cause (1). It is also used for purification purposes, as the brew often has a purgative effect. 

Normally ceremonies use altars, aka “mesas”, which include a collection of items such as stones and swords meant to strengthen the power of the healer and help heal afflictions such as ill health, bad luck, and enchantment (2). San Pedro is often used in conjunction with mapacho (a potent native tobacco), which is used to purify.  It can be taken alone, or in a brew called Cimora, where it is combined with a host of other plants such as Iresine, and toé (brugmansia sp) (3), among others.


San Pedro contains a cocktail of alkaloids, many of which may have unknown therapeutic effects. Mescaline is the most well-studied psychoactive alkaloid in San Pedro as well as many other cacti. It binds strongly and activates serotonin receptors, particularly the 5-HT2A and 5-HT1A receptors, leading to an increase in serotonin levels, which could account for some of San Pedro’s effects (4).

Mescaline also interacts with dopamine receptors, increasing the amount of dopamine available for nerve cells (5). Increased levels of dopamine caused by mescaline could explain the euphoric and emotional responses to San Pedro.

San Pedro is also gaining a reputation as a therapeutic tool, however research is limited. Though there are no current studies on San Pedro, specifically, there is some evidence to suggest that mescaline-containing cacti may improve the symptoms of addiction, and depression. 

" The purpose of ceremony is to strengthen the emotions and bring the patient back to equilibrium as well as empowering the body with medicine plants"
Rubén Orellana
"San Pedro teaches us to live in balance and harmony; it teaches us compassion and understanding; and it shows us how to love, respect, and honor all things."
Lesley Myburgh "La Gringa"


The consumption of San Pedro in religious ceremonies of South American Andean people is an important spiritual practice that dates back thousands of years. The use of San Pedro can be traced back to the Guitarrero cave in Peru where fossil remains of San Pedro have been dated as far back as 6800-6200 BCE.  San Pedro cactus representations have also been found on stone engravings, textiles, and ceramics in various archaeological sites, implying that a number of cultures: Nazca, Cupisnique (1500 BCE) Chimú, Lambayeque (750-1350 CE) and Moche (100-750 CE), and Chavín (1300 BCE) had knowledge of San Pedro practices (6).

The Western / Catholic colonization of South America resulted in hundreds of years of cultural, religious, and medicinal suppression at the hands of conquistadors. However, the tradition of San Pedro use was not destroyed, but transformed. it still plays a key role in the healing ceremonies of Northern Peru (7).

While Western botanists had previously discovered the effects of mescaline, it wasn’t until 1945 that they learned about the psychoactive qualities of San Pedro.

Mescaline was banned in 1970 in the US under the Comprehensive Drug Abuse Prevention and Control Act. However, San Pedro slipped under the radar. While it is still legal to own a San Pedro plant, extracting mescaline from it is an illegal act. Religious groups such as the Native American Church are however allowed to legally consume mescaline, like that from San Pedro, when used in religious ceremonies (8).

San Pedro and mescaline have gained in popularity in the West recently thanks to its psychoactive and cognitive effects that have potential therapeutic effects. Mescaline was even researched as far back as the ’50s for its therapeutic potential, with some transformative psychotherapeutic effects seen even months after treatment (9).

There is a need for research on the healing potential of San Pedro.  Mescaline, the most prevalent alkaloid San Pedro, has known therapeutic benefits including: general improvements to wellbeing, mental, and spiritual health. In addition, there is also evidence that mescaline-containing cacti may be useful in treating addiction symptoms.

Mescaline in San Pedro itself is non-addictive and may be a helpful tool in treating withdrawal symptoms in addicts.

  • A review of studies evaluating psychedelic drugs including mescaline in the treatment of addiction dependency. The review found that there is evidence to suggest that mescaline may aid addiction recovery and that the interaction of mescaline with the serotonin system may be responsible for some of this effect. Depressed serotonin levels are often seen in individuals suffering from addiction and so mescaline’s activation of serotonin receptors may play a role in reducing addiction symptoms (10).

  • A review of the use of mescaline in Native American Church ceremonies found that individuals who abuse alcohol and opiates but also participate in mescaline ceremonies show no symptoms of addiction. It is thought that mescaline is structurally similar to alkaloids that are found in the brain during alcohol intoxication, indicating that addiction treatment may be possible with plants rich in such alkaloids or mescaline (11).

As with all psychedelic plants, San Pedro carries within it the potential for a very powerful experience. The most likely risk associated with San Pedro is the “bad trip” (anxiety, fear, paranoia).  It is critical to carefully consider your mindset, intentions, and safety and comfort of the environment before engaging in any activity that will expand your awareness, as this will profoundly affect the experience.

Another important consideration, is the integration of the experience into your daily life.  While taking San Pedro, or other psychedelics, unconscious material may be brought to the surface during the session and if it is not worked through or integrated properly, may lead to negative emotions or experiences after the session has ended (12).

When taking San Pedro, exercise extreme caution if:

  • You have a family history of mental illness, or psychosis
  • Are pregnant, or breastfeeding- mescaline has been linked to fetal abnormalities
  • Have a heart condition or high blood pressure
  • Have liver issues


Side effects of San Pedro may include (13,14):

  • Nausea/vomiting
  • Visual hallucinations
  • Increased heart rate
  • Dizziness
  • Diarrhea
  • Headaches
  • Excessive Sweating
  • Tremors
  • Paranoia
  • Seizures
  • Amnesia
  • Suicidal thoughts – rare


Prescription drugs like  insulin, barbiturates or physostigmine, may increase the toxicity of mescaline. A large dose of mescaline in the presence of hyperinsulinism could prove fatal, extreme caution is warranted when mixing insulin and mescaline. In addition, caution is advised if you are currently taking an MAOI (15).

It’s highly recommended that individuals discontinue use of antipsychotic/depressants before use.

For more info on drug combinations visit tripsit.


Addiction Potential

The addiction and dependence risk for mescaline is negligible (16), however tolerance can develop quickly (17).

Like any substance, San Pedro can be abused, used in ways that compromise the safety of the individual and others.  Frequent use of San Pedro  may cause difficulty in adjusting back to reality, especially if it is being used as an escape from reality, rather than a tool to help improve wellbeing.


Long-Term Effects

In one study, researchers examine the long-term effects of a mescaline-containing cactus in Native Americans (18). It has the same active psychoactive compound (mescaline) in it as San Pedro, although different alkaloids in both plants are said to cause slightly different effects. The researchers concluded that “no evidence of psychological or cognitive deficits among Native Americans using peyote regularly in a religious setting.” The researchers were very clear to state that these results don’t necessarily translate to a recreational psychedelic user.


Harm Reduction Measures

  • Know why you are using San Pedro

  • Consuming San Pedro with an experienced practitioner can help assure your physical safety and help with appropriate dosing. The cactus isn’t dangerous, but cliffs, lakes, and wildlife can be!

  • Know what you are taking. Some brews may contain toé, this admixtures can have serious negative side effects, and in some cases may be fatal

  • Avoid initiating intimate contact with others whom you are not regularly intimate with

  • Don’t drink and drive, and avoid anything to do with vehicles and heavy machinery should be avoided

  • Prepare all foods that require a knife prior to using San Pedro to reduce potential accidents, then store all sharp tools in a secure location away from participants

  • Use San Pedro in a space you feel safe and comfortable in

  • Breath deeply and relax


For Basic Info on San Pedro visit ICEERS

Visit the Third Wave for the Ultimate San Pedro Guide

The Beginner’s Guide to Healing with Huachuma (San Pedro) @ Entheonation