How Long Does LSD (Acid) Stay in Your System?

LSD, often called acid, is a hallucinogenic drug that is illegal. It affects your perceptions for several hours and is detectable on drug screening tests. Learn how long it will stay in your system affecting you and how long it can show up on toxicology drug screens.

How Long LSD (Acid) Affects You After a Dose

LSD is usually swallowed as a capsule or liquid or absorbed in your mouth on a paper square.

Users feel the effects of LSD 20 to 90 minutes after taking a dose, peaking at two to four hours, and diminishing over six to eight hours. The effects can last up to 12 hours. Flashbacks can occur without warning, even days after taking a dose of LSD.

The common effects of LSD on body systems other than the sensory and mood effects are increased blood pressure, heart rate, and body temperature, which can result in dry mouth and sweating. The user may feel dizzy or sleepy and have a loss of appetite and nausea. Effects on the muscular systems include numbness, weakness, and tremors.

While on an LSD acid trip, the user can have rapid emotional shifts, intensified and distorted sensory experiences, and changes in the perception of time. If a large dose of LSD is taken it can produce some very unpleasant effects, sometimes called a "bad trip." But some users can experience a bad trip no matter what dosage they consumed. LSD can produce delusions and visual hallucinations, which can cause some users to panic. Users can experience severe, terrifying thoughts and feelings of despair, fear of losing control, or fear of insanity and death.

One long-term but the rare danger of LSD use is a condition called hallucinogen-induced persisting perceptual disorder (HPPD) in which flashbacks persist and produce distress or impairment for the user in social or occupational functioning.

How Long LSD Stays in Your System

An indication of how long LSD stays in your system is that it is broken down and excreted in the urine.

LSD can be seen in the urine within eight hours of a dose and the breakdown products are excreted for up to five days. LSD, like many other drugs, can be detected with a hair follicle drug test for up to 90 days.

How soon LSD it eliminated depends on your metabolism and factors such as how much you weight, whether you are well-hydrated, and how healthy all of your body systems are.

Keep in mind that if you have any other drugs in your system, they may be detectable on drug screens for longer than LSD and might influence how long LSD stays in your system. You cannot be assured of the purity of an illegally manufactured drug and there may be other detectable substances in LSD doses.

Bottom Line

LSD affects your mind and body significantly for at least 12 hours after a dose. You cannot be assured of the dosage and purity of an illegally manufactured drug purchased illicitly and this can influence how long you feel the effects and how long it remains in your system.

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Article Sources

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Additional Reading

  • Toxicology Screen: MedlinePlus Medical Encyclopedia. NIH MedlinePlus. Updated 1/26/2015.
  • Hallucinogens and Dissociative Drugs. National Institute on Drug Abuse.
  • Approximate Detection Times. Drugs of Abuse: Mayo Medical Laboratories.
  • Lysergic Acid Diethylamide (LSD). National Highway Traffic Safety Administration.