LSD

LSD belongs to a class of drugs called psychedelics – a term derived from the Greek for “mind-manifesting”. The story of LSD’s discovery in 1943 is something of a legend in the history of drug science. Albert Hofmann, a chemist at the Sandoz pharmaceutical laboratory in Basel, Switzerland, was looking for a drug that constricts blood vessels. One day, he accidentally ingested a small quantity of a compound he was studying, lysergic acid diethylamide (the initials LSD come from the German name).

He “immediately fell into a peculiar state of ‘drunkenness’, characterised by an exaggerated imagination,” he later recalled. Three days later, he deliberately took what he thought was a small dose, but it sent him on a powerful trip. Nevertheless, he cycled home, escorted by a colleague, and collapsed on the sofa, where he had an out-of-body experience.

The next day, Hofmann felt reinvigorated, and began to wonder if the profound shift in consciousness he experienced could be valuable in psychiatry. In the 1950s, Sandoz began giving out LSD, under the name Delysid, to psychiatrists to do research with. Early adopters such as the British doctors Ronald Sandison and Humphry Osmond found that it could induce mystical experiences that seemed to help shake people out of addictions and other patterns of negative thinking.

But interest in LSD soon spread beyond the medical community. Timothy Leary, a psychologist at Harvard University, evangelised about the drug’s spiritual power. As the drug became associated with the counter-culture movement and anti-authoritarian views, politicians got spooked. LSD was made illegal in the US in 1968, and research into its medical use was shut down.

Since the 1990s, research on psychedelics and their medical applications has resumed, but most of the attention has fallen on psilocybin, the active compound in magic mushrooms, which works in a very similar way. One small study found that psychotherapy with LSD helped to reduce anxiety in patients with life-threatening illness.

The first brain imaging study documenting the effects of LSD was published in 2016. It reported that LSD disrupts the activity of the default mode network, a group of brain structures thought to make up our sense of self. This may explain how the drug causes “ego dissolution” and feelings of oneness with nature and the universe.

LSD binds to receptors for the brain chemical serotonin. Its effects can last up to 15 hours, which might be because these receptors have a structure like a lid that traps the LSD molecule in place.

Some recreational users believe taking very small doses of LSD, a habit called microdosing, can improve their mood and productivity. So far, this has not been supported by rigorous scientific evidence.

LSD trips can be unpleasant and frightening, but it is one of the safest drugs there is. There have been no confirmed deaths from physical effects of LSD, and it is not addictive. Sam Wong