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Hallucinogens are drugs like LSD (lysergic acid diethylamide), mescaline (the active ingredient of the peyote cactus), and psilocybin (the active ingredient of psychoactive mushrooms). They cause profound changes in thought processes similar to a waking dream or temporary psychosis. Hallucinogens do not always cause hallucinations, so some specialists prefer the term psychedelic (mind-altering) for these drugs.

What are hallucinogens?


What is LSD?

LSD, lysergic acid diethylamide, is the most powerful psychoactive substance known to science. Tiny amounts of it, measured in micrograms-thousandths of a gram-produce powerful effects.

How did Albert Hoffman discover LSD?

LSD was discovered accidentally in 1943 by Albert Hoffman of Sandoz Laboratories in Switzerland. While working on the synthesis of medically potent alkaloids, he began having strange sensations.

As he wrote later, in his journal:

Last Friday, April 16, 1943, I was forced to interrupt my work in the laboratory in the middle of the afternoon and proceed home, being affected by a remarkable restlessness, combined with a slight dizziness....In a dreamlike state, with eyes closed...I perceived an uninterrupted stream of fantastic pictures, extraordinary shapes with intense, kaleidoscopic play of colors. After some two hours this condition faded away.

Hoffman speculated that some of the substance he was working on, LSD-25, had contacted his fingertip and was absorbed through the skin. He was working for a pharmaceutical company, so a drug with such strong psychological effects could be very important.

If LSD-25 had indeed been the cause of this bizarre experience, then it must be a substance of extraordinary potency. There seemed to be only one way of getting to the bottom of this. I decided on a self-experiment.

Hoffman deliberately drank a solution containing LSD. An hour and a half later he began his "most severe crisis."

...My surroundings had now transformed themselves in more terrifying ways. Everything in the room spun around, and the familiar objects and pieces of furniture assumed grotesque, threatening forms. They were in continuous motion, animated, as if driven by an inner restlessness. The lady next door, whom I scarcely recognized, brought me milk-in the course of the evening I drank more than two liters. She was no longer Mrs. R. but rather a malevolent, insidious witch with a colored mask.

...I was seized by the dreadful fear of going insane. I was taken to another world, another place, another time. My body seemed to be without sensation, lifeless, strange. Was I dying? Was this the transition? At times I believed myself to be outside my body...

By the time the doctor arrived, the climax of my despondent condition had already passed. My laboratory assistant informed him about my self-experiment, as I myself was not yet able to formulate a coherent sentence. He shook his head in perplexity, after my attempts to describe the mortal danger that threatened my body. He could detect no abnormal symptoms other than extremely dilated pupils....

Now, little by little I could begin to enjoy the unprecedented colors and plays of shapes that persisted behind my closed eyes. Kaleidoscopic, fantastic images surged in on me, alternating, variegating, opening and then closing themselves in circles and spirals, exploding in colored fountains, rearranging and hybridizing themselves in constant flux. (Hoffman, 1980, p.15)

Why did Hoffman doubt LSD would ever be used as a "recreational" drug?

Hoffman probably took a relatively large dose of LSD. The symptoms he experienced are typical of a "trip": kaleidoscopic images, feelings of being in a different reality or outside the body, and (in a "bad trip") a fear of going insane, paranoid ideas about health problems, exaggerated fears and anxieties. After such experiences, Hoffman never suspected LSD would become a so-called recreational drug. It was too powerful, and its effects were not pleasurable in any simple sense of the term. Hoffman saw LSD as a possible tool for artists or psychiatrists-one that would reveal the normally unseen depths of the mind through a sort of temporary insanity.

Under what circumstances are "bad trips" rare?

LSD is notorious for producing traumatic "bad trips" in some people. However, these experiences are rare when the drug is given in pure form under controlled circumstances. The United States Army and CIA tested LSD on hundreds of subjects. When the research suddenly became public in 1975, due to a lawsuit by a man who claimed lasting ill effects from his participation as a subject, Army drug experts hastened to reassure the public that the research was safe and most of the subjects experienced no harm. Newspaper reports like the following appeared.

Army Says LSD Not Dangerous

What did the Army discover in its research on LSD?

Army experiments with LSD showed the drug is powerful but not addictive and it changes body cells less than caffeine, according to a top researcher involved in the program.

Dr. Van M. Sim said he personally had tried LSD.

He told a Pentagon news conference Wednesday only a few Army test subjects reported having after-effects from the hallucinogen.

The director of chemical warfare research at Edgewood Arsenal, Md. said LSD was administered to 585 volunteers, mostly soldiers but including some civilian Army personnel, over 12 years ending in 1967. The Army previously had said possibly 900 other persons were tested by outside contractors as part of the program.

...The study, Sim said, found LSD is a powerful drug that civilians might use for enjoyment. It also found "LSD is not physically addictive."

Despite doses as high as 2,400 micrograms per hundred pounds of body weight, only seven volunteers reported aftereffects, he said, because their selection was carefully controlled and "it was a lot different from the civilian drug culture." ("Army says LSD not dangerous", 1975)

The Army studies used healthy, young subjects; they used a pure form of the drug; the subjects took the drug in an atmosphere of social approval, with medical experts on hand. All this makes it hard to compare the Army results with unsupervised recreational use of the same drug.

What did a task force conclude, after 14 years of research on the effects of LSD?

Federal research money for investigating LSD and other psychedelics ceased to be available in 1975 just as the Army and CIA research became public. There was still great interest in using LSD as a psychiatric tool, but after the 1970s little research was done on the drug. LSD was re-classified at that time as a Schedule 3 drug, a classification reserved for the most dangerous substances. This made it difficult for researchers to obtain permission to do research on LSD.

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