Traditional Medicine Of The Andes: Trichocereus Pachanoi (San Pedro)

Dive into the cultural importance and traditional medicinal use of the mescaline-bearing San Pedro cactus.

“After Jose invokes all the appropriate powers, including a number of Catholic saints, he takes a glass of an extract from the San Pedro cactus (Trichocereus pachanoi). His two assistants receive their doses and then each patient, one by one, is called before the "altar" to do the same.”

This passage from medical anthropologist, Donald Joralemon, describes the healing work of Peruvian San Pedro curandero (native healer), José Paz Chapofian. Here, consumption of the San Pedro medicine was likely preceded by the embellishment of a ceremonial altar or “mesa” with an assemblage of symbolic objects, including pre-Hispanic ceramics, Catholic icons, and medicinal herbs, before rhythmic rattle shaking, whistling, and singing set the ritual’s wheels in motion. 

José, like many Peruvian healers that utilize the psychedelic qualities of San Pedro’s chemical constituents, performs ritual sessions twice weekly in the seaside town of Huanchaco and the small coastal city of Lambayeque further North. José’s shamanistic work requires him to tap into a steady, trance-like state of consciousness, during which he communicates with animal and plant spirits and journeys to distant locations. 

This healing modality likely seems a tad obscure to the average Westerner, who, having been exposed only to the traditional Western medical system, is, through no fault of their own, ignorant of the possibility of there being alternative means of diagnosing and healing the sick, much less combating “bad luck” and removing “black magic curses.”

Not only does San Pedro shamanism exist, however, but archaeological evidence suggests that this ancient magico-religious healing ritual could be up to 10,000 years old.

What is San Pedro?

San Pedro, also known as huachuma (meaning “removing the head”), and commonly referred to as a “grandfather medicine,” is a fast-growing, multi-stemmed cactus native to the dry and rocky landscapes of the Andes Mountains, stretching from Ecuador to Argentina. San Pedro is one of the more widely renowned psychedelic plants employed in the context of ritual healing. 

An artistic rendition of the Andes Mountains.

San Pedro is a long, deep green, night-blooming species that grows wild and contains the classical psychedelic compound mescaline (3,4,5-trimethoxyphenethylamine) at rates ranging from 0.025% to 4.7% of dry cactus weight. Mescaline is the main psychoactive constituent in several other medicinal cactus species, including peyote (Lophophora williamsii), and was the first classical psychedelic to pervade mainstream Western culture. 

Originally misclassified as Opuntia cylindrica, the correct name for San Pedro is Echinopsis pachanoi, scientifically speaking. However, this is subject to change. Some passionate botanists are sticklers for accurate taxonomical classification and may insist on the strict usage of either Trichocereus or Echinopsis, but most people are rather indifferent. You can generally use either Trichocereus pachanoi or Echinopsis pachanoi to convey that you are speaking about San Pedro cactus.  

In the 16th century, Spanish conquistadors recorded the ceremonial consumption of San Pedro by the natives, and the accompanying Christian missionaries referred to Huachuma as “the plant with which the devil deceived the Indians of Peru in their paganism.” Once indigenous inhabitants of South America had been Christianized, ritual consumption of Huachuma was incorporated into emerging Christian belief systems, and it was renamed after Saint Peter who is said to hold the keys to heaven as promised to him by Christ, which is suggestive of the plant’s power to facilitate access to alternate experiential realms of great peace and harmony. 

Experiential Elements of San Pedro Rituals 

As briefly touched upon above, the characteristic features of a traditional San Pedro ceremony imply the existence of a radically different worldview among shamanic practitioners than is typically held by health professionals in the West. It is said that San Pedro possesses an innate intelligence that communicates to users upon ingestion, which is why indigenous healers often refer to the cactus as a "plant teacher."

In 1998, a former psychedelic researcher at Harvard and co-author of the famous volume ‘The Psychedelic Experience: A Manual Based on the Tibetan Book of the Dead’ by the name of Ralph Metzner described the following cardinal features that are foundational to the effectiveness of San Pedro rituals in a paper titled Hallucinogenic Drugs and Plants in Psychotherapy and Shamanism

The Curandero 

The role of the curandero, curandera (female healer), shaman, or guide, is always described as absolutely central. Curanderos have extensive personal experience in the use of mind-altering plant medicines. They are experts in facilitating initiatory healing experiences for the sick and unfortunate and training aspiring curanderos to perfect the practice. In most San Pedro rituals, the curandero does most of the singing, and this singing profoundly shapes the nature of the experience.

The curandero’s uptempo singing in combination with rhythmic drumming is considered essential to the success of the healing process. Rhythmic chanting and drumming are said to support transitions between visions and minimize the likelihood of getting trapped in frightening experiences.

Having an intimate understanding of the effects of San Pedro, curanderos are in an excellent position to facilitate safe visionary journeys for ritual participants.

Artistic rendition of a curandero.

Different Levels of Healing

According to scholars of indigenous medicine, the psychedelic experience induced by San Pedro, and the sacred context in which it is safeguarded, can be therapeutic and insightful on physical, psychological, and spiritual planes. Though, indigenous healers don’t make such analytical distinctions.

Traditional San Pedro-facilitated healing experiences typically have three main variations: one is the removal of a “dago,” a vengeful toxin that is commonly believed to have been implanted via air or potion by a “brujo” or evil sorcerer; the second is the retrieval of a lost fragment of the "soul”; and the third is the experience of being physically destroyed, and then regenerated as a healthier, more robust living being. 

Hidden Knowledge

In shamanic traditions, San Pedro is said to be capable of providing access to hidden knowledge via divination. The concept of divination mirrors that of what Western medicine calls diagnosis, however instead of identifying the nature of a modern illness like depression, San Pedro curanderos determine from where and from whom a particular poisonous implant came, the whereabouts of a person’s “lost” soul fragments, and the combination of herbs and other plant medicines that should be administered as a remedy. 

Access to Alternate Realms 

So too in shamanic contexts is there a feeling and perception of access to metaphysical realms referred to as the “inner world” or “spirit world,” which may be described as “non-ordinary” or “alternate” states of consciousness by psychedelic researchers in the West.

Access to metaphysical realms is oftentimes said to have been achieved by journeying on the back of an animal or being carried by a large bird. Irrespective of the means of transportation, the usual boundaries between the world of the ordinary and the world of the non-ordinary seem to dissolve during such experiences. 

Entity Encounters 

As is commonly reported by users of another naturally-occurring classical psychedelic, DMT, an experience with San Pedro may involve interactive encounters with seemingly autonomous, nonmaterial, spirit beings or entities. These spirits are believed to be associated with animals of special significance among indigenous cultures (e.g., a jaguar or serpent), plants or fungi, certain settings (e.g., a rainforest), deceased ancestors, and other scenarios and concepts.

The jaguar is a powerful spirit totem in shamanic tradition.

Users may have the experience of actually morphing into or identifying with a particular plant or animal spirit or other extraterrestrial entity. Considered allies, such spirits are thought to play an instrumental role in the healing that takes place in traditional San Pedro ceremonies, however, contact with evil spirits that need to be defeated is also possible. Spirit encounters are invariably of a personal, religious, spiritual, or transcendental nature.

Interestingly, and perhaps somewhat expectedly, encounters with spirits are more common in dark environments, and so San Pedro rituals almost always take place at night. 

Characteristic Effects of Trichocereus Pachanoi

It can be easy to over-consume San Pedro because the effects of cactus-derived mescaline can take several hours to kick in, though most people start to feel effects within 15-40 minutes. Unlike super-potent psychedelics like LSD, mescaline requires a high dosage to produce its characteristic effects, the duration and intensity of which are modified by a variety of factors including administration route, dosage, mindset, setting, and individual physiology. 

After consuming San Pedro, the come-up period can be marred by unpleasant nausea, vomiting, sweating, and dizziness, though these effects are temporary and typically not as intense as those produced by the medicinal Amazonian brew ayahuasca.

Once these rather inconvenient autonomic symptoms subside, the ensuing 8-14 hour-long San Pedro experience gradually takes the form of a highly spiritual, dreamlike intoxication typically characterized by flashes of brilliantly colored light, kaleidoscopic visuals, hallucinations, bliss, euphoria, feelings of unity, synesthesia (blending of the senses), and formal disorganization of time and space. 

Users may also re-experience significant scenes from their personal life, shifting emotions, a softening or complete loss of self-consciousness, and dissolving of the boundaries between self and other, thereby, in the words of Metzner, releasing one into the “awesome worlds of cosmic consciousness.”

As a consequence of San Pedro’s highly variable mescaline content, and the fact that curanderos typically only serve high doses to “severe cases,” there are relatively low rates of psychedelic experiences documented in the ethnographic literature. Relatedly, in considering the indigenous ritualistic use of peyote, the so-called “father of ethnobotany,” Dr. Richard Evans Schultes, surmised that the importance of peyote’s visionary properties may have been exaggerated – and perhaps the same is true of San Pedro. 

San Pedro Rituals: A Final Word 

According to Canadian anthropologist Douglas Sharon – a shamanism scholar who has studied pre-Columbian shamanic practices in South and Central America for over 40 years – the San Pedro cactus has the power to open users' unconscious mind “like a flower and render the forces that made him sick visible and susceptible to the curer's therapeutic powers."

Ritual participants experience the ceremony and all of its fascinating experiential elements as purifying and cleansing, their body’s being purged of harmful toxins aggressively implanted by bad-intentioned forces of evil.

Despite its cultural importance and medicinal status of great antiquity, we are unlikely to see the therapeutic properties of San Pedro or synthetically-produced mescaline being re-investigated scientifically any time soon. This is largely because mescaline is a schedule I substance, but also because its long duration of action, low potency, and relatively high production cost render the introduction of San Pedro- or mescaline-facilitated therapy into clinical practice unlikely.

Perhaps removing the San Pedro cactus from the shamanic context in which it is revered as sacred, and introducing it to lifeless hospital hallways, would be a mistake. Though, the reconciliation of indigenous and Western medicine geared toward the flourishing of the human species does seem a perfectly reasonable proposition, if not an appropriate next step. Here’s hoping Western medicine will awaken to the therapeutic value of indigenous healing systems. 

In any case, should one wish to experiment with San Pedro voluntarily, they are best advised to make themselves aware of the plant’s ambiguous legal status. The legality of the use of San Pedro in the United States is questionable, because, unlike peyote, Trichocereus pachanoi is not listed as a Schedule I substance, even though mescaline is. That said, cultivation, use, and distribution of certain entheogenic plants, including San Pedro, has recently been decriminalized in several US states and cities. 

As always, users should practice great caution when self-experimenting with psychedelic substances, ensuring they are in a good mindset and a safe, supervised setting. 

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