How Long Does Weed (Marijuana) Stay in Your System?
It varies according to dose
Weed, also known as marijuana or cannabis, is usually detectable in bodily fluids for 1 to 30 days after last use. As with other drugs, it may be detectable in hair for several months.
Weed detection windows depend on how much you smoke or ingest, as well as how often. In general, higher doses and more frequent use are associated with longer detection times.
For daily users, cannabis may be detectable for several months after last use. The longest-reported detection times are more than 90 days.
Read on to find out the detection windows for cannabis in urine, blood, saliva, hair, and more.
Drug tests measure weed and its by-products, or metabolites. These metabolites remain in your system long after weed’s effects have worn off.
According to Mayo Clinic Proceedings, weed is detectable in urine for the following amounts of time after last use:
- Occasional users (up to three times a week): 3 days
- Moderate users (four times a week): 5 to 7 days
- Chronic users (daily): 10 to 15 days
- Chronic heavy users (multiple times a day): more than 30 days
Cannabis metabolites are fat-soluble, which means they bind to fat molecules in your body. As a result, it can take some time for them to leave your system.
According to an article in Therapeutic Drug Monitoring, weed is typically detectable in the blood for 1 to 2 days. However, in some cases, it’s been detected after 25 days. Chronic heavy use increases the length of time that it can be detected.
Weed is detectable in the bloodstream within seconds of inhalation. It’s distributed to the tissues. Some of it is reabsorbed in the blood and broken down. Its metabolites may remain in the bloodstream for days.
Blood testing may be used in laboratory settings or to indicate recent use of weed.
According to a 2014 review on cannabinoids in oral fluid, weed is detectable in saliva for the following amounts of time after last use:
- Occasional users: 1 to 3 days
- Chronic users: 1 to 29 days
Weed can enter the saliva through smoking and exposure to smoke. However, its metabolites are only present in saliva when weed has been smoked or ingested.
In jurisdictions where weed is legal, oral fluid may be used for roadside testing.
Hair follicle tests assess drug use for up to 90 days . After use, weed reaches the hair follicles via small blood vessels. Trace amounts may remain in the hair.
Since hair grows approximately 0.5 inches per month, a 1.5-inch hair segment taken close to the scalp can provide a window of weed use for the past three months.
The active ingredient in weed is a chemical substance called THC, which stands for delta-9-tetrahydrocannabinol. THC that enters your body is absorbed into the bloodstream.
Some THC is temporarily stored in organs and fatty tissues. In the kidneys, THC can be reabsorbed into the bloodstream.
THC is broken down in the liver. It has more than 80 metabolites, but the most significant ones are 11-OH-THC (11-hydroxy-delta-9-tetrahydrocannabinol) and THCCOOH (11-nor-9-carboxy-delta-9-tetrahydrocannabinol).
Drug tests look for these metabolites, which stay in your body longer than THC. Eventually, THC and its metabolites are excreted in urine and stool.
A number of factors affect how long weed stays in your system. Some of these factors, such as your age, gender, and body mass index (BMI), aren’t related to the drug itself, but to how your body processes and metabolizes the drug.
Other factors are related to weed and how you use it. This includes how much you take (dose) and how often (frequency). Higher doses and more frequent use tend to increase the amount of time it takes to eliminate weed from your system.
More potent weed, which is higher in THC, may also stay in your system for longer. Weed that’s ingested may also remain in your system slightly longer than weed that’s smoked.
There isn’t much you can do to speed up the amount of time it takes for weed to leave your system.
Once it’s entered your system, your body needs time to break it down. Exercising, eating healthy, and staying hydrated may help, but not drastically.
There are a number of weed detox remedies and kits available on the internet. Many require drinking a lot of water to dilute your urine, and then using herbal supplements such as creatinine or vitamin B-12 to mask the dilution.
These kits don’t work reliably.
Weed’s effects appear quickly, usually within 15 to 30 minutes after smoking. It can take one or two hours to feel weed’s effects when it’s ingested.
Weed’s active ingredients produce a short-term “high.” Common effects include:
- sense of well-being
- sense of relaxation
- feeling that time is slowing down
- giggling or chattiness
- altered sensory perception
Other short-term effects include:
- inability to focus
- increased appetite
- coordination problems
- rapid heart rate
- dry mouth and eyes
- feeling sick or faint
- anxiety or paranoia
In rare cases, high doses of weed can cause hallucinations, delusions, and psychosis.
Smoking or ingesting weed on a regular basis can have additional effects on your mind and body. You might be at an increased risk of developing:
- cognitive impairments
- memory impairments
- learning impairments
- cardiovascular diseases, such as heart disease and stroke
- respiratory illnesses, such as bronchitis and lung infections
- mood disorders, such as depression and anxiety
- hallucinations and psychosis
If you use weed while you’re pregnant or breastfeeding, there’s a greater chance that your baby will have birth defects or problems with brain development.
Weed’s short-term effects start to taper off after one to three hours. Some effects, like memory problems or trouble sleeping, can last a few days.
Researchers don’t know how long the effects of chronic use last. Long-term effects can last days, weeks, or months after weed use has ended. Some effects may be permanent.
Weed may stay in your system anywhere from several days to several months after last use. Detection windows depend on the drug test used and other factors, such as whether you smoke or ingest weed on a regular basis.
Weed is detectable in bodily fluids for up to 30 days after last use. For daily users, weed may be detectable for several months after last use. The longest-reported detection times are more than 90 days. Here’s how long it’s detectable via each type of drug test, whether you can metabolize it faster, and more.
How Long Does Marijuana Stay in Your System?
- Medical Author: Divya Jacob, Pharm. D.
- Medical Editor: Dr. Pallavi Suyog Uttekar, MD
What is marijuana?
Marijuana, also known as weed, pot, or ganja, is a medicinal plant of the Cannabis family. It contains a psychoactive compound known as tetrahydrocannabinol (THC) that has major intoxicating effects. The leaves, seeds, stems, or roots, are mainly used for intoxication purposes. Marijuana preparations are usually smoked in pipes, joints, or water pipes (bongs). Marijuana users also add it to food or brew it as a tea. Marijuana is the most abused substance in the United States. Approximately, 11.8 million young adults used marijuana in 2018.
What happens when you smoke marijuana?
Marijuana, when inhaled, exhibits short- and long-term effects on the brain.
- After smoking marijuana, THC passes from the lungs into the bloodstream, and it is carried to the brain and other organs. The effect is generally felt after 30 minutes to one hour. THC activates parts of the brain, which produce the primary psychoactive and the intoxication effects. Other effects felt are:
- Altered senses
- Distorted sense of time
- Mood swings
- Impaired memory
- Psychosis (disconnected from reality)
- Impaired coordination
- Difficulty in thinking clearly
- Increased appetite
Long-term effects result in some permanent changes to the brain, such as losing mental abilities and functioning.
Other physical changes are:
- Breathing problems
- Increased heart rate
- Problems with child development during and after pregnancy
- Intense nausea and vomiting
How long does marijuana/weed stay in your system?
Detectable amounts of THC may remain in the body for days or even weeks after use. Upon consumption of marijuana, THC is absorbed and stored by various body tissues and organs. The drug is primarily broken down by the liver. The by-products formed by the breakdown are immediately cleared via urine. However, THC stored in the body tissue gets continuously released back into the bloodstream over time, where it continues to be broken down by the liver and cleared in urine until all of it is depleted from the body. In a chronic user, the excretion rate of THC through urine is less, so it builds up in the liver.
When will marijuana show up on a drug test?
Several tests are used to detect the presence of marijuana. They include:
- Saliva test: A person can test positive for marijuana for up to 34 to 48 hours after the last marijuana use.
- Urine test: Infrequent users test positive for one to three days, moderate users can test positive for 7 to 21 days and a heavy user can test positive for a month or longer after the last marijuana use.
- Hair test: Marijuana can be detected in a hair test for up to 90 days.
- Blood test: Marijuana will be visible in a blood test for up to 36 hours.
What are the treatments for marijuana abuse and addiction?
Marijuana addiction is mostly treated in a rehabilitation center. Behavioral therapies that are effective in treating marijuana addiction are:
- Motivational enhancement therapy (MET): Motivates the individual to give up a marijuana addiction.
- Cognitive-behavioral therapy (CBT): Teaches the user to stop using the drugs and ways to avoid or manage other problems.
- Contingency management (CM): Involves exchanging vouchers as a reward for not taking drugs.
Although medications may not be effective in treating addictions, some antidepressant medications may help with managing withdrawal symptoms and preventing relapses.
Marijuana, also known as weed, pot or ganja, is a medicinal plant of the Cannabis family. It contains a psychoactive compound known as tetrahydrocannabinol (THC). THC activates parts of the brain, which produce the primary psychoactive and the intoxication effects.