LSD (lysergic acid diethylamide), also commonly known as acid, is a psychedelic drug that gained popularity in the 1960s as part of the counterculture revolution. Originally created in 1938 by Albert Hofmann from lysergic acid, which is found in the ergot fungus, LSD was researched as a potential psychotherapeutic medication in the 1950s and 1960s until it was classified as a controlled substance in the 1970s and all research was discontinued. There has been renewed interest in the use of the drug as part of treatment for depression, anxiety, and addiction, and much research is currently being devoted to documenting its clinical effects. The effects of a good LSD “trip” commonly include feelings of euphoria, visual or auditory hallucinations, and a sense of connectedness to the universe; a bad trip can include feelings of anxiety, paranoia, irrational fears, and other distressing emotional states. It is currently illegal to possess or ingest LSD for recreational purposes.

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An Introduction to LSD

LSD, or lysergic acid diethylamide, is a synthetic drug with potent psychedelic properties. Commonly known as acid, it was originally derived from compounds found in ergot, a fungus that grows on rye. 

LSD was first synthesized by a Swiss chemist named Albert Hofmann in 1938, who was testing various lysergic acid compounds as stimulants. During further testing in 1943, Hofmann somehow accidentally ingested some LSD, and the resulting dreamlike hallucinations he experienced intrigued him enough that he purposely ingested the drug several more times, eventually concluding that it might be useful in psychiatric therapy. 

While LSD was used and studied in a therapeutic setting during the 1950s and early 60s, its adoption by the 60s counterculture movement as a recreational, mind-expanding drug branded it as dangerous in the eyes of the U.S. government. This led to its designation as an illegal substance in 1968 and a subsequent ban on any scientific studies into its potential medicinal uses. 

What does LSD do to your brain? 

LSD acts on multiple receptors in the brain, including adrenergic and dopamine receptors, but most specifically it binds with certain serotonin receptors, causing hallucinations. It also encourages connectivity between parts of the brain that don’t normally interact much. According to one researcher, LSD “flattens the energy landscape between different parts of the brain, bringing them closer together,” which can allow for more flexibility in typically rigid thought patterns.

What happens during an LSD trip? How long does LSD stay in your system?

LSD is typically taken in “tab” form, which is a small piece of paper soaked in LSD and dissolved beneath the tongue. Others drip the liquid onto sugar cubes, or add it to squares of jelly called “window panes.” Once ingested, it takes 30 to 90 minutes for LSD to take effect. As LSD is one of the longest-acting psychedelics, it can take up to 12 hours for its effects to completely wear off.

There are a range of physical and psychological effects associated with LSD, including:

An LSD experience varies widely based on how much of the drug is taken, as well as on the “set and setting” in which it is used—that is, the mindset of the individual before taking the drug and the physical environment in which the drug is taken. 

Can LSD be used for therapy? What conditions does it treat?

After years of government resistance to research, LSD and other psychedelics are now being studied in the treatment of a variety of mental health conditions. Studies suggest that the cognitive flexibility associated with taking LSD can be beneficial for a variety of conditions, including: treatment-resistant anxiety and depression (especially in cancer patients), addiction, and possibly even PTSD.

Is LSD legal?

Like other psychedelics, LSD is still listed as a Schedule 1 drug in the United States, meaning it is illegal to manufacture, possess, or distribute without a license. While the movement to decriminalize the possession of psychedelics is gaining steam, only Oregon has currently extended this to include LSD, meaning that full prosecution for LSD-related offenses is still pursued in all other states. Internationally, laws vary.

What is a “bad trip” on LSD like?

There are a variety of difficult and even dangerous experiences that an LSD user can encounter, including paranoia, heightened anxiety, confusion, delirium, or panic attacks brought on by the visions, sensations, and emotions induced during an LSD session. Experiences like these are commonly known as “bad trips,” and they’re always a risk when taking psychedelics, especially at higher doses. While the symptoms usually fade once the “trip” ends, they can be seriously distressing and may require medical attention. For this reason, it’s extremely important to have someone with you who remains sober to act as a “trip sitter,” either a trusted friend or a medical/therapeutic professional. 

Can you microdose LSD?

Microdosing psychedelics, including LSD, is becoming increasingly popular. It involves taking one-twentieth to one-tenth of a recreational dose in order to enhance everyday life, boosting things like creativity, energy, and focus. But microdosing is still largely unproven; researchers are just beginning to focus on it with a few studies currently in the works, including a self-reporting study championed by several big names in psychedelics like Paul Stamets and Mark Haden.

What are the long-term effects of LSD? What are acid flashbacks?

There have not been many studies done on the long-term effects of LSD, though one study did not find any identifiable links between the drug and mental health issues or suicide. That being said, there are two known potential long-term issues with LSD:

  • Acid flashbacks: Flashbacks involve disturbed sensory perceptions (sight, sound, taste, touch, or smell) that occur long after a dose of LSD has worn off, but can feel like the person has taken the drug again. These can be either pleasant or unpleasant in nature, and may or may not significantly disrupt a person’s day; people usually recognize that what they are experiencing isn’t real, and the flashback typically only lasts for a minute or two. Flashbacks are relatively rare.
  • Hallucinogen persisting perception disorder (HPPD): When flashbacks become more frequent, distressing, or don’t go away, it may be a case of HPPD. This condition is even more rare than regular flashbacks, and has never been seen within psychotherapeutic trials of LSD, but can potentially be treated by a doctor. HPPD may last for as little as a few months or for as long as a few years.

People with a family history of psychosis or schizophrenia are advised against taking LSD, as it may induce a psychotic episode. All psychedelics do carry some risk, so it is very important to assess your personal degree of risk before use. 

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