The effects of LSD on your mind can be unpredictable, powerful, random and sometimes very frightening.
Dr Trisha Macnair last medically reviewed this article in March 2010.
The effects of LSD on your mind can be unpredictable, powerful, random and sometimes very frightening.
Dr Trisha Macnair last medically reviewed this article in March 2010.
LSD stands for lysergic acid diethylamide. It's a synthetic chemical manufactured from natural sources such as a fungus called ergot, which grows on rye (more formally called Claviceps purpurea).
It was developed in 1938 by the Swiss chemist Albert Hoffman, who was trying to develop chemicals that might be of use as medicines. He did nothing with it until 1943, when he experimented with it on himself and discovered its mind-altering effects.
LSD is one of the most powerful known hallucinogens. It isn't clear exactly how LSD acts on the brain to cause distorted perception, as research has been limited. But it seems to block the brain neurotransmitter serotonin (which regulates functions including perception, behaviour, hunger, mood and many more) and activate dopamine, another neurotransmitter.
It's also known to stimulate the sympathetic nervous system causing:
LSD is commonly known as acid, but also goes by a variety of names often influenced by the way it is presented for sale - typically it is sold as a tiny square or spot of blotting paper that has been soaked in LSD. These papers may be printed with pictures or logos, which inspire a name. It may also be sold as liquid drops or tiny pellets.
Names for LSD include blotter, dots, squares, tabs, smilies, stars, windows and fruit.
LSD is a Class A illegal substance with severe penalties for possession or sale.
LSD causes intense hallucinations - in other words, a distortion of reality. The world around the user becomes changed - light, colours and sounds are altered and even mixed up, and there may be visions of people or creatures or landscapes which don't actually exist. Even time itself seems to change, slowing down or speeding up.
These experiences are known as a trip and its nature is very unpredictable. It may be peaceful, gentle, colourful and musical, or it may be very unpleasant and aggressive or just anxiety-inducing, leaving a person fearing for their sanity.
The nature of the trip is influenced to some degree by the individual's own mental state, the mood they are in and how comfortable they are with the people around them. The drug can also induce rapid and intense emotional swings.
The trip starts between 20 minutes and an hour or two after taking the LSD. Because the onset and nature of its effects are uncertain, it's not uncommon for people to take a second tablet thinking it isn't having much effect on them, only to find they are then experiencing a double dose. The effects usually last about 12 to 15 hours.
Because of its hallucinatory properties, LSD was embraced by the hippy culture of the 1960s as a way to explore your inner self and achieve higher states of enlightenment. It also saw a resurgence in popularity with rave culture in the 1990s.
LSD isn't physically addictive, although people can develop tolerance to it, rapidly needing more to achieve the same effect but there are no physical symptoms of craving or withdrawal.
Psychological addiction - a dependency on experiencing the effects of the drug - may develop, especially when people use it to escape an unpleasant reality.
LSD does not have a risk of physical addiction. However, a variety of other important risks have been associated with the drug:
Treatment may be needed to help someone get through the effects of a bad LSD trip. This usually means simply being supportive and reassuring, placing them in a quiet dark room with little sensory stimulation. Rarely, if a person is extremely agitated, doctors may suggest using a sedative.
In the long term, most people who use LSD stop taking it as their social circumstances change or they lose interest. There aren't usually any withdrawal symptoms as it's not physically addictive.
Sometimes people need psychological support to move away from their habit or to deal with the effects of a bad trip. Talk to your doctor if you feel you need help.
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