Moonlight Cactus: The medicine & mystery of San Pedro

Chances are good that the name mescaline comes with a reputation from anyone who has heard it. This psychoactive compound is found in a variety of cacti, including peyote (Lophophora williamsii) and San Pedro (Echinopsis pachanoi or Trichocereus pachanoi). The ancient use of San Pedro in Peru is verified as far back as 1300 B.C. The plant is believed to have been utilized since the dawn of the Andean civilization. Stone carvings in an old temple of the Chavín people unearthed depictions of the plant. It is theorized that the Nazca Lines, the infamous geoglyphs of southern Peru, were used it as “sacred maps” for voyages into altered states of consciousness (Third Wave).

The name San Pedro derives from Christian mythology, taken from the legend of Saint Peter who holds the key to heaven. However, San Pedro ceremonies also have pagan associations, due to the strong ritual of imbibing the plant at night. The plant is used in ceremonial settings in order to make the subconscious "open like a flower", much like the cactus bloom that emerges under the light of the moon.

Spanish Catholic missionaries arrived in the 16th century and observed that shamans would drink San Pedro and remained “without judgement and deprived of their senses, and they see visions that the devil represents to them..." (Plants of the Gods) The colonizers labeled the sacred medicines as diabolical, and subsequently prohibited ceremonies with the plant. Yet colonial oppression was no match for those carrying on their traditions. The tribes held their ceremonies in secret, reportedly instructed by the plants themselves. (Cassels BK).

Catcus bloom at Emerald Pharms. Photo by Leslie Carrow

The cactus is generally found growing in altitudes between 6-9 thousand feet. Shamanas voyage to high altitudes in the Andes mountains to collect the cactus near sacred lakes and lagoons. The journey is seen as a form of purification. People with various illnesses will also make yearly pilgrimages San Pedro territory.

San Pedro varieties come in six, seven, or eight ridges. The seven-edged variety is the most common. The most sought after type in the Andean region is the four-sided variety, which has a high content of mescaline and other alkaloids. Four ribs are considered to have special powers as they represent the four winds (Plants of the Gods).

San Pedro is traditionally planted close to the home and is known to protect the family and provide a “peaceful coexistence of parents and children” (Armijos, C, et al). San Pedro grows vigorously in a home garden or natively in the wild, which provides an advantage to peyote, its endangered and slow-growing counterpart. However, areas ripe with psychedelic tourism may result in unsustainable harvesting practices of San Pedro, especially if the peyote supply continues to wane. (Third Wave)

Unlike cacti coming from desert landscapes, San Pedro has a special dualism with water. It can handle months without rainfall, while at the same time it is acclimated to getting large amounts of water which expands its ridges. It can withstand many elements and can survive in varying climates.

San Pedro blooms are a special sight to behold. People report that the cactus may require a decade of growth before its first bloom. The flower opens at night and they last only a day or two before wilting. Large numbers of San Pedro are planted in California, as it thrives in the sunny climate and grows quickly when given daily watering.

Mescaline & legality

Peyote generated scientific interest in mescaline and other compounds. Mescaline was first synthesized by Ernst Spaff in 1919 and then manufactured as a research chemical by Merck, a pharmaceutical company that produces around 98 different pharmaceutical drugs, including various vaccines and birth control. (Rucker, James 2018) Mescaline is a tryptamine which falls into a similar drug class as psilocybin, DMT, and LSD. (Niamh NicDaéid, 2019).

Prior to 1945, botanists were unaware of any mescaline-containing cacti besides peyote. It is believed that mescaline is produced by these plants as a defense tactic to prevent animals from eating them. San Pedro contains variable amounts of mescaline, and significantly less than peyote. (Chabaco 2014)

San Pedro is legal to cultivate for landscaping purposes in the USA. The cactus is not specifically listed as a Schedule I controlled substance (unlike peyote, which is classified). However, once extracted or consumed, San Pedro is classified as mescaline and falls under Schedule I. Despite its centuries of use, mescaline containing plants and others in the Schedule I drug classification (including cannabis) are not considered to have any medical benefit (Third Wave).

Medicinal use

While mescaline is the psychoactive active component of San Pedro, the cactus also contains other active compounds which may contribute to some of its therapeutic properties. Some examples are anhalonidine, which has a mild sedating effect and hordenine, an antibiotic. The plant is used as a wound healer and anti-inflammatory. (Crosby, DM). The cactus pulp can be cooked and placed on a wound in order to prevent infection and soothe irritation. Sometimes San Pedro is made into a water infusion mixed with other plants to treat anxiety in Peru. The infusion is taken for several days until the patient begins to feel better. (Chabaco, A.)

For psychoactive purposes, the cactus brew is traditionally boiled in water for seven hours, and then imbibed in a ceremonial setting in order to induce visualizations. This medicine is used as a tool to find the root of an ailment. Shamans generally take the cactus themselves and also give it to patients during nighttime rituals. Shamans will sometimes mix San Pedro with other psychoactive plants to produce a brew known as Ciroma (Plants of the Gods).

In Saraguro communities, ceremonies with the cactus are performed to regain health for those with an illness where traditional medications are not effective. Intentions of the ceremony may be to gain love, money, or to find lost objects. The plant is also used for divination, to counteract witchcraft, to gain personal success, and as a remedy for alcoholism. In traditional settings, the healer acts merely as a facilitator, to encourage the participants to open to the healing gifts of the medicine. These rituals make no distinction between the body and the mind. Healing is as much mental as it is physical. Shamans generally seek the root cause in the spiritual plane and may recommend other conventional medications during the process.

Ingesting the beverage may lead to purging (vomiting or diarrhea), which is believed to remove the obstacles in the way of someone’s health.  The use of purgative plants cleanses the body and prepares it for a deeper healing subsequently. Some people experience an emotional release that can lead to tears, which is considered a remedy for the spirit (Chabaco, A., Third Wave).

San Pedro is sometimes used to connect people to one another, tapping into the “oneness” of the universe or healing rifts in the familial cloth. It also possesses empathic qualities which some users have reported grants a sense of universal connection and an ability to work out issues in community (Erowid). Some also speak to the ability to express their emotions more freely and empathize with other people’s struggles.

Biochemically, mescaline has been found to have affinity for dopamine receptors and to activate serotonin. (Cassels BK) This may explain some of its potential influence on the psyche. Serotonin is an important neurotransmitter that affects feelings and how information is processed. It is believed to regulate mood, memory, gut activity, and sleep. Serotonin is also a tryptamine. Many antidepressant medications are thought to work by boosting serotonin levels in the body. Dopamine is an important chemical found in the brain, which when triggered can produce the feelings or love or affection. (Wikipedia Dopamine & Serotonin)

Potential applications for San Pedro and mental health

The search for mental health treatments cannot omit the dark history when psychoactive substances were used for interrogation tactics by the US government. In the 1940s and 50’s the US military began using MDMA, peyote, LSD and others for psychedelic-assisted interrogation tactics. They were looking for the so called “truth serum” which would make people reveal secret information and to manipulate the behavior of those being detained. Peyote was later pursued for its “truth telling” attributes. The military tested it and several other entheogenic compounds on psychiatric patients in New York state. (Passie T.)

Afterwards, a few studies were conducted on mescaline for mental health. One performed in 1955 gave 25 schizophrenia patients 500 mg of mescaline by injection. While three patients demonstrated temporary remission of symptoms, and one patient achieved “complete remission”, psychotic symptoms worsened in the remainder of patients. The researchers concluded that “mescaline was not a clinically effective agent in schizophrenia” (Rucker, J.).

Further research on mescaline or other psychoactive substances stopped in 1967, when they were classified under Schedule I of the 1967 UN Convention on Drugs. Since then, there has been a resurgence in interest on mescaline for mental health purposes. A 2013 study found that participants using mescaline (and cacti containing the compound) throughout their lifetime has less psychiatric medicine prescriptions than those who did not. It also found that mescaline/peyote correlated with a decreased fear of closed spaces (agoraphobia) and a lower rate of some psychotic symptoms. (Krebs, T.)

Mescaline is generally regarded as a safe substance. A lethal dose has never been pinpointed and there have been no reported deaths from taking it. A 2005 study looked at the ceremonial use of peyote in Native Americans and found no long-term harmful effects.

A grassroots movement has popped up in recent years that advocates for the use of entheogenic substances in microdose form. This enables the user to ingest the medicine without experiencing pronounced mind-altering effects. Some benefits of microdosing mescaline that some users have reported are: relief from anxiety, mood enhancement, self-reflection, creativity, empathy, mental clarity, motivation, and sociability. (Third Wave: Microdosing). Some people find that a short term microdosing with San Pedro can get to the root of their problems and help them find solutions that may not have been as clear to them before.

First-hand knowledge vs. scientific discovery

Based on the interesting applications of mescaline on the human experience, the therapeutic qualities of San Pedro warrants further investigation. Yet due to the illegality of mescaline in the USA, obtaining a Schedule I license to study it is extremely difficult. Often times science has to look at one “active” compound of a plant medicine to examine it rigorously. However, plants provide a wide array of compounds, and their healing attributes cannot be distilled down to one component. Studies on the mescaline found within San Pedro would not be able to give the full picture on the medical uses of cactus.

However, a lack of scientific evidence does not negate the centuries of use of San Pedro by indigenous people. Sometimes the Western world lacks a proper lens in order to be able to view plant medicines as they would be in their traditional context. Those working the plant have seen the healing benefits first-hand. No amount of scientific evidence, or lack thereof, could negate it.

Ideally, further study on the plant would benefit the good of all. But whether or not scientific investigation would inevitably lead to its misuse is worthy of consideration. We live in an era of of botanical medicine exploitation and the overtaking of indigenous land for economic profit. This includes psychedelic tourism, with ayahuasca being a primary example. Sometimes a plant may beckon an individual and that may indicate a good time to work with its medicine. Or perhaps there is benefit to simply growing a plant to witness its gifts, and not to ever harvest it.

The plant kingdom gives infinite opportunities to explore and learn, and cactuses provide insight into a special world. Like any plant, they are far greater than the sum of their parts. And despite what is known about them, their mystery must include a massive respect for their healing abilities.

By Sarah Russo