Bronze Age humans, 3,000 years ago, got high on hallucinogenic plant alkaloids so powerful and dangerous that even psychedelic users of today avoid them, according to a new study. The humans may have had out-of-body experiences or thought they were growing fur or feathers as a result of consuming the anticholinergic substances atropine or scopolamine.

Symptoms would have started more mildly with dilated pupils, dry skin and a racing heart. As the trip set in, the user would have experienced full-on delirium, or the inability to differentiate between hallucinations and reality.

Menorca Strands

Researchers found the chemicals, along with the stimulant ephedrine, inside strands of hair buried deep in a cave on the Spanish island of Menorca, not far from an earlier burial site. One or more persons had buried the hair in a special wooden box decorated with concentric circles, which may have signified “inner vision” related to drug-induced states of consciousness. The capsule-makers had dyed the strands of hair red with ochre or wild madder or Balearic box and sealed them in the containers with string.

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Made of olive tree wood, the box had three chambers and sat buried alongside five similar boxes, four containers made from antlers, a bronze blade and hairpin, and numerous other artifacts.

What was the purpose of this cache? The researchers suggest it was a type of time capsule intended to preserve older, more established customs carried out, originally, by shamans. At around 2,800 years ago, the people of Menorca and the surrounding islands began to grow in number and abandon the old burial sites, such as the cave, Es Càrritx, where some 200 individuals had been buried.

Since about 4,000 years ago, the people of Menorca had treated death grandly, building dolmens, megaliths, cairns and rock-cut tombs, the study says, before utilizing the local caves.

Powerful Chemicals

Because the study performed a chemical analysis and not a genetic analysis of the hairs (due in part to a lack of hair bulbs), we now know more about the individuals’ past drug use than who they were. Researchers sliced the hairs into cross-sections and found that the people had used the drugs repeatedly over a period of about a year prior to their deaths.

Today, psychedelic users often avoid deliriants such as atropine and scopolamine because of the unpredictable, nightmarish experiences they can cause at large doses, not to mention intense anxiety and dysphoria. But during the Bronze Age, European shamans would have had to use the plants available to them, the study suggests, including such nightshades as mandrake, henbane, thorn apple and joint pine.

The researchers say the study provides “the first direct evidence of ancient drug use in Europe,” and it follows a paper that found opium alkaloids inside Bronze Age pots from the Eastern Mediterranean, a form of indirect evidence.

At sufficient doses, both atropine and scopolamine can kill the user, but they retain medical uses, nonetheless. Doctors use atropine to reduce saliva during surgery, and to accelerate the heart rate when needed, and scopolamine protects against post-surgery nausea and vomiting.

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