LSD

LSD is a potent hallucinogenic drug. It is made from lysergic acid, which is found in a fungus that grows on rye and other grains.

LSD can have long-lasting impacts on your brain and emotional state. This is true even if you use the drug only once.

On this page

• About LSD
• Short-term effects of LSD
• Long-term effects of LSD
• Risks related to LSD use
• Substance use disorders and withdrawal

About LSD

LSD is also known as

• dots
• acid
• blotter
• window pane
• mellow yellow
• California sunshine

LSD stands for lysergic acid diethylamide. It causes hallucinations and has very unpredictable effects.

In its pure form LSD is a white, odourless and slightly bitter crystalline powder. On the street it is often sold as small squares of LSD-soaked blotting (absorbent) paper. These squares each contain 1 dose of LSD and are taken by mouth. It is generally held on the tongue or swallowed.

LSD can also be sold as a powder or as capsules and tablets. The powder may be made into miniature powder pellets called microdots. These are taken by mouth.

LSD crystals may also be dissolved into liquid. This liquid can be sold in small breath-freshener droppers or applied to various substances, including:

• gum
• candy
• cookies
• sugar cubes
• gelatin squares
• postage stamps

Rarely do people inhale or inject LSD.

LSD is controlled under Schedule III of the Controlled Drugs and Substances Act. Activities such as sale, possession, and production of LSD are illegal unless authorized for medical, scientific or industrial purposes.

Short-term effects of LSD

LSD’s effects are felt gradually, within 30 to 60 minutes after taking it. The effects peak in 2 to 4 hours and then fade over a period of 10 to 12 hours. People refer to their experience under the influence of LSD as a "trip."

LSD use can lead to short-term mental and physical effects.

Mental effects

On LSD you may see, hear or feel things that are not really there (hallucinations). LSD affects your brain by:

• changing your senses, moods and thoughts
• distorting perceptions of yourself and of the world around you
• altering what you hear, taste, feel and smell (brighter colours, sharper sounds)
• mixing up your senses, so that you “hear” colours and “see” sounds

LSD produces vivid visual effects called pseudo-hallucinations. You are aware that these things are not real. Whether or not you experience actual hallucinations is related to:

• the amount of LSD you take
• your mood, thoughts and surroundings

Other effects of LSD can include:

• difficulty concentrating
• feeling weightless or heavy
• altered or impaired memory
• feeling disconnected from your body
• extreme changes in mood, from
  • joy to desperation
  • well-being to terror or aggression
  • calmness to anxiety or depression
• impaired judgment of distance, time or speed
• fear of losing control, fear of death, panic attacks

Deaths associated with LSD are usually the result of accidents caused when you sense or see something abnormally. This can lead to errors in judgment. For example, a person may be convinced that they can fly or can walk through traffic unharmed.

Physical effects

You may also experience physical symptoms, such as:

• sweating
• dizziness
• sleeplessness
• numbness or tremors
• widened (dilated) pupils
• loss of appetite, nausea or dry mouth
• decreased coordination and weakness
• increased blood pressure and heart rate
• increased or decreased body temperature 

Long-term effects of LSD

The health risks related to using LSD frequently are more mental than physical. The drug can have long-lasting effects on your brain and emotional state. Sometimes the effects continue for years after you stop using LSD. These include:

• paranoia
• psychosis
• flashbacks
• depression

Risks related to LSD use

If you use LSD while you’re pregnant, you increase the risk of:

• spontaneous abortion
• birth defects in your infant

You may have a “bad trip,” especially if you have taken high doses. These may be frightening and may include:

• paranoia
• loss of boundaries
• a distorted sense of self

Impaired judgement during “bad trips” may lead to death or traumatic injuries from risk-taking behaviour.

In certain cases you may experience frequent or overly intense psychedelic events. These may bring on abrupt “flashbacks,” where you relive the previous experience.

Flashbacks are fairly common among hallucinogen users and may cause significant stress. When they persist and distress you for a long time, they are known as Hallucinogen Persisting Perception Disorder. This disorder is relatively rare. 

Another risk of LSD use is a psychotic reaction, although again it is rare. Some symptoms of psychosis include:

• delusions
• hallucinations
• disorganized speech
• disorganized behavior

If you are predisposed to or have existing psychiatric conditions there may be an elevated risk of side effects.

Over the last 10 years the availability of a large number of new psychoactive substances, including drugs similar to LSD (analogues) has increased. The harms associated with the new drugs are not yet known but it is clear that they are not without risk.

Substance use disorders and withdrawal

LSD does not cause physical dependence. Unlike with some other drugs, you are not driven to use LSD even if you use it frequently. Even though you do not have physical withdrawal symptoms, you can develop a psychological dependence on it.

If you use LSD regularly your body may become tolerant of its effects. This means you need to take more and more of the drug to experience the same effects. Tolerance to LSD can develop very quickly.

If you keep using LSD for several days, no amount of the drug will produce an effect. Sensitivity to the drug's effects only returns if you do not use it for 3 to 4 days.