The specific length of time that LSD remains in your system depends on a wide range of factors, including the dose you took, the purity of your LSD, and your metabolism. Additionally, LSD remains in different parts of your body for different lengths of time, such as within the hair, blood, and urine.
The following clearance times exist for the average adult person who has consumed LSD for various parts of the body:
- Blood: Researchers say LSD can be detected in blood for up to 24 hours following consumption of the drug.
- Hair: A typical hair test can detect drugs taken up to 90 days earlier. In 2015, researchers determined that these tests work in detecting LSD.
- Urine: LSD can be detected in the urine for up to five days.
Quick Facts About LSD Half-Life
Half-life refers to the length of time that it takes for the concentration of a particular substance that has been consumed and entered the bloodstream to be reduced by 50%.
Researchers say LSD’s half-life is about 3.6 hours. This means that after this duration, half of the LSD that one has consumed has been metabolized and cleared from the body.
A drug’s half-life is relatively fixed, but how long the drug might last in your body can be influenced by several factors, including the following:
- How you took LSD and its distribution through your body
- The drug’s metabolization rate
- Your age
- Medications you use
- Your organ health
How Is LSD Metabolized?
LSD is a powerful hallucinogenic drug that can significantly alter perception. Individual metabolism is an important factor in determining how long LSD remains active.
Your body produces several chemicals to break down drugs, including CYP2D6, CYP1A2, and CYP2C9. If you produce too much or too little of these substances, the drug may move through your body faster or slower than expected.
In research conducted in 2021, researchers found common variants in these chemicals in people who took LSD. Those with little CYP2D6 had LSD half-lives that were 75% longer than those with functional CYP2D6 production. They had more powerful reactions to the drug, and it seemed to last longer.
You may not know that your body doesn’t produce enough critical chemicals until you have an unusual reaction to the drug or it appears in a drug test for longer than it should.
The metabolic process involved in the elimination of LSD involves cytochrome P450 enzymes, which are integral in the metabolism of toxins like drugs. The primary metabolic pathways involved in LSD removal include the following:
- N-demethylation: This consists of the removal of the methyl group from the LSD molecule, leading to the production of compounds like nor-LSD.
- Hydrolysis: This involves the metabolism of the chemical bond within the LSD molecule via water, leading to the production of diethylamide and lysergic acid.
- Glucuronidation: This process consists of the addition of a molecule of glucuronic acid to LSD and its metabolites, helping in their removal via urine.
After LSD is metabolized, it is eliminated from the body primarily through the kidneys via urine.
Is LSD Legal?
LSD is a Schedule I substance under the Controlled Substances Act. That means officials have determined it has a high potential for abuse, and it has no currently accepted medical use in the United States.
Since LSD is illegal, it’s impossible to get it from a reputable source, like a pharmacist or laboratory. Instead, you must buy the drug from dealers, and you could get arrested for having or taking the drug.
Breaking Down LSD in Your Body
The half-life of LSD is about 3.5 hours. The following chart reflects the timelines by which LSD will be detectable on certain types of drug tests:
Type of Drug Test | Timeline |
Blood | 6–12 hours |
Urine | 1–3 days |
Hair | Up to 90 days |
Saliva | 1–2 days |
It is important to note that these time frames vary by individual. There is no way to “beat” a drug test. If you need to take one, the best way to pass it is to avoid drug use altogether.
Signs of LSD Abuse
Drug abuse refers to the use of a drug in any way other than as medically prescribed, so any form of LSD use would be considered abuse in most contexts. There are some places where laws related to LSD use have become more relaxed. There is also some evidence to show that LSD, in controlled doses, can be effective for addressing some mental health issues. If you are using LSD recreationally, it is considered abuse.
Some of the most notable signs of LSD abuse include the following:
If you regularly abuse LSD and are unable to stop this use, it’s a sign that addiction has formed.
- Hallucinations
- Altered perception
- Mood alterations
- Changes in thought processes and patterns
- Dilated pupils
- Increase in body temperature
- Elevated blood pressure
- Elevated heart rate
- Reduction in appetite
- Nausea
- Vomiting
- Insomnia
- Impulsive behavior
- Social withdrawal
- Preoccupation with locating LSD and/or the discussion of psychedelic experiences
If you regularly abuse LSD and are unable to stop this use, it’s a sign that addiction has formed.
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