Anatomy of a Ritual

Natural History, July, 2001 by Jared Diamond

In several New World cultures, the enema was the technique of choice for taking hallucinogenic drugs. The practice was based on sound physiological principles.

Ritual intake of alcohol and hallucinogens by enema used to be widespread among Native American tribes and is still practiced today by some. It was performed both by hunter-gatherers in the Amazon jungle and by the Maya, the most advanced indigenous civilization in the New World. But the custom may seem puzzling or bizarre to many people today. After all, if you're disposed to mind-altering drugs, it's easy just to swallow, smoke, sniff, or lick them. Why go to the trouble of taking them by enema?

The answer does not have to do with the unique beliefs of exotic cultures but with basic principles of intestinal physiology, applicable to all of us. My own research specialty as a physiologist consists of trying to figure out how our intestine is adapted for doing what nature meant it to do. Rectal administration of drugs seems to be the reverse of what's natural. How could the outcome not be disastrous if we use an orifice specifically adapted for expelling chemicals to admit them instead? But recent advances in our understanding of digestive physiology lead me to conclude that Native American enema devotees knew what they were doing. Until the modern invention of hypodermic syringes for intravenous injection, the rectal route for hallucinogens offered special advantages.

Most Natural History readers, insofar as they think of enemas at all, doubtless associate them not with optional entertainment but with unpleasant medical necessity. Physicians routinely prescribe enemas to clean out a patient's lower intestine before an operation or a diagnostic procedure such as a colonoscopy. As far back as the time of the ancient Sumerians, medical enemas were used to relieve constipation by washing out intestinal contents, and to eliminate parasitic intestinal worms by instilling an antiworm drug, or vermifuge (same etymology as "centrifuge," from the Latin fugere, to flee, but in this case the flight is from the worms, Latin vermis, rather than from the center). For instance, rectally administered tobacco infusions--whether employed against pinworms, roundworms, tapeworms, or threadworms--proved an effective vermifuge in sixteenth-century Europe.

These two Old World uses of enemas are easy to understand. In both cases, substances were administered by rectum, rather than by mouth, because the aim was to reach the lower intestine. There was no intent for the substances to reach the brain, and every intent for them not to. That's where traditional New World practices differed. American Indians used enemas only to administer mind-altering drugs. The rectum served not as a dead-end street but as a highway to the broad meadows of the body and brain. The enema was elevated from an uncomfortable, cold-blooded, results-oriented medical procedure to a delicious, quasi-religious ritual.

New World natives used many mind-altering drugs ranging from alcohol and nicotine to hallucinogens, and several of the latter were avidly embraced by drug users in the 1960s. Cocaine comes from the leaves of an Andean tree; mescaline, from the peyote cactus of Mexico and Texas; LSD analogues, from morning glory seeds; and psilocybin and psilocin, from Mexican mushrooms. With these or any other mind-altering drugs, the user's basic problem is how to get the drug to the brain. Today one can just use a needle and syringe to inject a drug into the bloodstream, but other means were needed in the days before hypodermics. While all such methods rest on the principle of getting the drug in contact with some body surface through which it will be absorbed into the blood, many choices of surface present themselves.

The most familiar choice is the small intestine, the upper stretch of our intestine just below the stomach. Coiling back and forth, the small intestine has a total length of about twenty-three feet. Its inner surface has innumerable microscopic and submicroscopic folds; smoothed out, it would cover about 5,000 square yards, comparable to the area of a football field. This enormous expanse makes the small intestine well adapted not only to its natural function of absorbing almost all the nutrients we ingest in food but also to the abnormal function of absorbing swallowed drugs.

Smoking is a popular route of drug intake for basically the same reason: microscopic folds also give our lungs a football-field-sized expanse through which to absorb oxygen and remove carbon dioxide. Still other absorptive surfaces are the tongue, the lining of the mouth, and the lining of the nose, reached through licking, chewing, and sniffing, respectively. Indians took drugs by all these still familiar routes plus two now unfamiliar ones: applying drugs to the skin and delivering them through the eyes, either by dripping them as liquids or blowing them as smoke.

The remaining absorptive surface discovered by Native Americans was the lower part of our intestine, known variously as the large intestine, colon, or rectum. To reach the other surfaces I have mentioned, all you have to do is swallow, inhale, lick, chew, or sniff (or simply expose an expanse of flesh or an eyeball). The rectal route, however, requires some mechanical props.