How Long Does Weed Stay in Your System? Facts and FAQs

How Long Does Weed Stay In Your System

THC is just like any other compound that goes through your body’s metabolism processes. But you may want to know exactly – how long does marijuana stay in your system? There is no specific answer to this question, all is individually. Like most other drugs, the duration that weed remains in your body depends on various factors. These factors include:

  • Usage frequency
  • Level of THC in the weed
  • Hydration levels
  • Lifestyle
  • Bodyweight

Detection times also vary depending on the drug test used. Metabolites will remain longer in the hair than most drug testing samples. Here are the four types of drug tests and their average detection times:

  • Hair (30-90 days)
  • Urine (3 – 7 days)
  • Saliva (1 – 3 days)
  • Blood (3 hours – 2 days)

How Long Does Weed Stay In Your System

How the Body Metabolizes THC

Once Tetrahydrocannabinol (THC) enters the body through the lungs (in case of smoking), it’s absorbed into the bloodstream, scattering it to tissues throughout the body. Once the compound reaches tissues in the brain, it creates that “high” effect, familiar to cannabis users and desired by them.

Edibles stay a bit longer in the liver, but eventually go through the same process. In the chart below, you can see two products that can aid you to get rid of weed residues: Toxin Rid and Mega Clean.


Toxin Rid

  • Three-part detoxification system with pre-rid tablets, liquid detox, and dietary fiber
  • Specifically designed for people with HEAVY toxin exposure
  • Starts working as fast as one hour
  • Rids your blood, urine, and saliva of unwanted drug toxins
  • 100% money-back guarantee
See Deal →

Mega Clean + PreCleanse Pills

  • Minimizes your toxin levels in one hour, effective for up to five hours with the maximum effect at three hours
See Deal →

THC metabolism has two phases to clean weed out:

Phase 1: THC Hydroxylation & Oxidation

Specific enzymes in the body hydroxylate portions of the cannabinoid, creating a metabolite called 11-OH-THC. This compound is responsible for the psychoactive effects of cannabis. 11-OH-THC is then oxidized by the same enzymes, turning it into THC-COOH, an inactive metabolite that can no longer bind to cannabinoid receptors. THC-COOH is exactly the metabolite that lab workers detect on a drug test.

Phase 2: THC Leaves the Body

In this phase, THC-COOH converts into a THC-COOH-glucuronide molecule, which the body excretes through urination and defecation.

Types of Drug Tests

As SFHIV/San Francisco Department of Public Health claims, there are four drug testing methods, and each one differs in process, required samples, and detection windows. Of course, you really want to know how long does it take weed to leave system. But, sorry to say, there’s no definite answer as it differs for each individual. Factors like body weight, dosage, and frequency determine how long does THC take to get out of your system. You may refer to this handy calculator to get an estimate.

Let’s go over each drug testing method.

Urine Drug Test

Urine tests, also known as urinalysis, include visual and chemical examinations of a urine sample to look for drug compounds that stay in pee long enough to be detected.

Marijuana is metabolized by the liver. The liver breaks in into metabolites, and after that they leave your body with urine and feces. About 20% of the metabolites are excreted through the urine and 80% in your stool. When you take a urine drug test, it looks for these metabolites. You can get your test results back from a urine test in as little as ten minutes and the test is pretty cheap. Because of this, most employers, law enforcement, and families use urine tests for THC detection. So, for how long can weed be detected in your urinary system?

How Long Will THC Stay in Urine?

The amount of time that weed stays in your urinary system depends on the amount you consume, how long you have been using, your metabolism, your size, and your body fat percentage. If you are a heavy user, meaning you use at least once per day, THC can be detected in your urine for up to 30 days. This is because your body can only metabolize THC at a certain rate. If you are a chronic user, more THC will remain in your body, and it will stay in fat cells. Because of this, people with a higher body fat percentage store THC in their system for longer. Boosting your metabolism, exercising and being well-hydrated can help your liver and kidneys clear marijuana from your system faster.

Do you want to know, how long does weed stay in your system? Well, THC stays in your system for a urine test between 3 and 30 days. Several factors affect the length of time marijuana remains detectable, including use frequency, body mass, hydration levels, and urine acidity.

In most drug tests the most significant factor that determines duration is the frequency of use. As you can see from the chart of THC detection times in urine, more frequent marijuana use means longer detoxification times.

Marijuana Use Frequency Detection Window
One-time use 1 – 3 days
Moderate use (three times a week) 5 – 7 days
Daily use 7 – 14 days
Heavy use 14 – 90 days (90 for hair test)

Are There Ways to Pass a Urine Test?

THC in the urine will naturally clear away over time, but you can hasten the detoxification process. The most efficient way is by taking detox supplements, like Toxin Rid’s dietary supplement program. Toxin Rid can get THC out of your system fast. It works by accelerating the body’s natural detox process, removing weed detectable in urine in time for urinalysis.

Supplements can be effective, but they need time to work. Some people resort to “backup plans” like using synthetic urine. One product that’s often used is TestClear’s artificial Powdered Urine Kit. This product has a formulation that simulates human urine, which can test negative on a standard urinalysis.

Blood Drug Test

Blood tests are another method for exposing marijuana use. In this method, testers analyze blood samples in a lab for traces of THC and other drug metabolites. As with urine, weed stay in your blood system long enough for detection.


Toxin Rid

  • Three-part detoxification system with pre-rid tablets, liquid detox, and dietary fiber
  • Specifically designed for people with HEAVY toxin exposure
  • Starts working as fast as one hour
  • Rids your blood, urine, and saliva of unwanted drug toxins
  • 100% money-back guarantee
See Deal →

Mega Clean + PreCleanse Pills

  • Minimizes your toxin levels in one hour, effective for up to five hours with the maximum effect at three hours
See Deal →

A blood test can be more accurate than a urine test for THC, and the blood test is difficult to trick. However, it is not used as often as a urine test for THC. This is because weed traces are not detected in blood for as long as it can be detected in a urine test. By the time an employer or law enforcement agent decides to test you for THC, it will probably be out of your system.

How Long Will THC Remain in the Blood?

A blood test also takes a lot more time to result and uses more resources than other tests. It takes equipment to draw your blood, and the blood must be sent to a special lab for testing. It will probably take a day or two to get your results, and it will cost the company a lot more money to run the test. Most blood tests are used to check for other substances or health problems rather than for weed. However, it is still a possibility, and you might find yourself asking how long does THC stay in your blood system.

Like urine, the amount of time that weed stays in your blood depends on your metabolism, body size, and frequency of marijuana use. When you smoke, marijuana levels in your blood peak just a few minutes and then rapidly decline. When you use edibles, the peak happens about an hour after ingestion before they decline. Whether you smoke or take an edible, THC will be completely out of your blood in about 4 hours after a one time use. If you use higher concentrations of THC over long periods of time, it can take as much as 48 hours to completely clear your blood from any trace of marijuana.

Marijuana traces remain in the blood for 3 – 4 hours for an infrequent user. Chronic or heavy (more than 1 time a day) use can increase this duration for up two days. Of course, other factors like the amount of THC in the weed and the person’s natural way of processing THC can impact how long does pot stay in blood.

Hair Follicle Drug Test

Follicle drug tests use hair follicle samples to root out drug use. Hair follicles have blood vessels where THC can pass through, making them detectable during a lab examination.

Hair drug tests have the most extended detection window among the other commonly used methods. So, the answer to a question “how long does weed stay in your system?” may really scare you. Testers can determine drug use from hair follicles for up to 90 days. The more frequently you are at using marijuana, the more accurate it gets.

How Long Does Weed Stay in Your Hair Follicles?

A hair follicle test is only used to check for long-term use of marijuana. If you smoked weed today, traces of THC would not show up in your hair for 7-10 days afterwards. This is because the THC is stored in the root of the hair, and hair grows so slowly. Exactly how long does weed stay in your hair follicles?

A hair test is an unreliable method for testing occasional use. Not very much THC is stored in the hair follicles, and having one or two edibles or smoking once may not even be detectable in the hair follicle test. If you use cannabis once a week or more, THC will be stored in your hair follicles and will continue to show up in the roots of your hair. Once the metabolites get into your hair follicles, they will stay there until you cut it.

Hair grows at a rate of about 0.5 inches per month. This means that if your hair is 18 inches long, you could have THC at the bottom of your hair follicle from three years ago. But don’t worry, the standard for testing is to use 0.5 inches to 1 inch from the root of the head, giving only about a two month window for detection. Remember that hair from anywhere in the body can be used. If you shave your head, your test will simply be delayed and repeated in a few weeks. THC can still be detected in new hair growth for 90 days.

Can You Cheat on a Hair Drug Test?

One of the most effective ways to detox hair follicles in time for a test is using a technique known as the Macujo Method. It involves using several products and ingredients to reduce the THC levels in the hair enough to test for negative.

One of the most vital components of the Macujo Method is popular among weed users. It is Old Style Aloe Toxin Rid shampoo, and you may know this product. Without this shampoo, this technique just wouldn’t be as effective as it’s supposed to be. Old Style Aloe Toxin Rid can detox your hair fast, and you can even use it as a standalone detox product without bothering with the entire method. But it won’t be that effective.

Saliva Drug Test

Saliva test, also known as a mouth swab drug test, uses saliva samples to identify the presence of marijuana and other drug metabolites. It typically involves using a sponged swab stick to swab the inside of the cheek or under the tongue.

How Long Does THC Stay in Saliva Glands?

A saliva test is usually taken when someone wants to perform an immediate test for THC. This is generally a test used by a highway patrol person or someone at the scene of a workplace accident. You and the person testing you will be able to see results within three minutes. The use of this kind of drug testing is expanding, because it is less invasive than blood, hair, and urine testing. It is also cheap, requires very little equipment, and can be performed at a moment’s notice. Saliva testing is a little bit less reliable than other testing strategies and a nervous person with a dry mouth can make this test more difficult and take longer to complete. Recent 2022 studies have shown that saliva testing is only about 80% accurate compared to 90% for urine and 95% for blood tests.

Like for the other tests, you might be curious how long does THC stay in saliva glands. Again, the detection window depends on your frequency of use. There are some misconceptions about saliva tests, and some people believe that edibles cannot be detected in the saliva as much as smoking can. This is not true. Both edibles and smoking can be detected in the saliva for several hours to several days, depending on how often and how much cannabis you consume. If you use marijuana daily and have used it for a long time, your saliva can carry traces of THC for up to a month.

Are There Ways to Pass a Saliva Test?

You can try to mask detectable weed residues in your mouth temporarily, using Toxin Rid Rescue Wash Mouthwash. This product is used just moments before the test and gives a 4-hour window of clean saliva. The manufacturer claims that THC becomes undetectable during that 4-hour window.


  • What Makes One a “Frequent” Cannabis User?

    You’re considered a frequent or heavy user if you smoke weed at least once every day. Moderate use means using cannabis every other day, 3-4 times per week.

  • Can You Force Metabolize?

    The metabolism rate varies from person to person. You can do a lot of things to boost your body’s natural metabolism, like exercise and frequent hydration.

  • Is It possible to Receive a False Positive Test for THC?

    Yes, receiving a false positive for a THC drug test is possible. Certain hemp-based foods and secondhand marijuana smoke inhalation can trigger a false positive.

  • How Long do Edibles Stay in Your System?

    Edibles stay in your system for the same amount of time as smoked marijuana. Up to 30 days in urine, 90 days in hair follicles, 48 hours in blood, and 4 weeks in saliva. If you have edibles once a week or less, the detection window is shorter, 3-4 days in urine, 4 hours in blood, and one day in saliva. The detection window for hair follicles doesn’t change as much depending on the frequency of use.

  • How long does it take for THC to leave your system?

    THC leaves your system through the urine and stool. It can be stored for a long time in your fat cells. Exercising to break up your fat cells can help metabolize the THC in your system more quickly. THC metabolites can be found stored in fat cells for up to 28 days after the last cannabis use.

  • How long does one smoke session stay in your system?

    For a first-time smoker, THC will stay in the system for about three days. If you continue smoking once a week or less, your body can keep up and will clear your system in three to four days after each session. Smoking three or four times a week extends the detection period to about a week.

  • What is THC?

    The marijuana plant dates back thousands of years. The first record of marijuana cultivation was found in Chinese records from the 28th century, and there has been a 3,000 year old Egyptian mummy found with traces of THC in its system. The cannabis plant is thought to be native to India. This amazing plant has hundreds of chemicals called cannabinoids. The most well-known of these chemicals is THC. So, what exactly is THC?THC, short for tetrahydrocannabinol, is the chemical in marijuana that causes most of the drug’s psychological effects. For several centuries, marijuana has been used as an alternative medicine in many cultures. Recently, it has become more popular in Western states as a treatment for nausea, chronic pain, and PTSD.

    THC attaches to cannabinoid receptors all over the body. In the brain, THC can affect thinking and reasoning, memory, movement, concentration, coordination, pleasure, and time perception. THC causes the brain to release dopamine, a chemical that makes you happy or even euphoric. It can also affect how information is stored and processed in your hippocampus, the part of the brain that helps you form new memories. In the immune system, THC works as an immunosuppressant and anti-inflammatory. This may be the reason for its pain-relieving effects.


Overall, how long does THC stay in your system? Well, it depends so much on your use, your weight, your hydration, and your metabolism. So, it is hard to know exactly how long THC will stay in your system. It is best to assume a longer time period to protect yourself from problems at work or with the law. THC stays for the longest in hair, up to 90 days, but these tests are not used very frequently. The most common test, a urine test, has a detection window of 7-30 days from last use.

Having a low body fat percentage and being well hydrated can make these detection windows shorter. For a blood test, 48 hours is plenty of time for your body to clear any toxins. You may need up to 4 weeks to completely clear your saliva of any THC metabolites. So, if you are only an occasional user and have an important event coming up, give yourself a few days to detox. With all these tips, you should pass your test without any problems.

This info given by San Francisco HIV health services


  • Moupali

    Director of Implementation Science and Evaluation Research in the HIV Prevention Section. Assistant Clinical Professor in the Divisions of Infectious Diseases and HIV/AIDS at San Francisco General Hospital at the University of California. Her manuscript has been cited as the basis for measuring CVL in President Barack Obama’s National HIV/AIDS Strategy (NHAS)