How Long Does Marijuana Stay in Your System?

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Table of contents

  1. Factors That Influence Retention
  2. How Long Marijuana Shows up on Drug Tests
  3. Can You Speed Up the Elimination Process?
  4. Frequently Asked Questions

Marijuana — also called cannabis or weed — can stay in your system for as little as a few hours to a month — or even longer. The time depends on the dose, consumption method, and health. If you take a drug test, the type of test will also factor into how long cannabis stays in your body. For example, marijuana is detectable in hair follicles for several months after use.

Factors That Influence Retention

The following factors affect how long marijuana and the psychoactive cannabinoid tetrahydrocannabinol (THC) stay in your system. 

Dose

Logically, higher doses of cannabis will result in longer THC retention periods. Microdosing is one way to reduce the impact of THC and minimize retention time. 

Frequency

If you consume cannabis daily, THC is more likely to stay active in your system for longer. People who consume marijuana infrequently are less likely to retain THC in their systems for long periods. 

Delivery Method

When you breathe in THC, such as through smoking, vaporizing, and inhalers, it passes through the lungs and immediately affects it. This effect usually lasts from one to two to three to four hours, depending on how much has been smoked/vaped/inhaled. 

Small doses of THC are not likely to last longer than a couple of hours, whereas a large amount of THC (e.g., using a THC concentrate through a dab rig) can last longer – three to four hours, or even eight hours if a potent concentrate has been used.

Other delivery methods, such as sublingual tincture, may last slightly longer than smoking marijuana. Consuming edibles also results in a longer retention time for many people. 

Body Fat

As cannabis metabolites are fat-soluble, they bind to fat molecules in the body. This means that cannabinoids stay in the body for quite some time, especially for people with high body fat percentages. 

For heavy users who ingest cannabis multiple times a day, THC metabolites can be detected for up to 90 days, usually in the hair and urine. 

Genetics

Age, weight, individual metabolism, levels of physical exertion, and genetics also affect how long cannabinoids stay in the system.

Strain Content

THC-dominant strains will naturally result in THC staying in your system longer than CBD-rich strains. Choosing a balanced ratio of 1:1 CBD:THC may help reduce the amount of time that THC stays in your system, but there is no guaranteed foolproof trick. 

How Long Marijuana Shows up on Drug Tests

The following are general guidelines for how long marijuana shows on drug tests. Be aware that slight variances may vary depending on your weight, body fat percentage, and experience level, among other vital factors. 

Urine Tests

Urine testing is one of the most common ways of testing cannabis. Cannabinoid metabolites are detectable in the urine for the following amounts of time after last use:

  • Infrequent users (once a week or less): one to three days.
  • Occasional users (three times a week): three to seven days.
  • Moderate users (four times a week): five to 10 days.
  • Daily users (once per day): 10 to 30 days.
  • Heavy daily users (multiple times a day): 30-plus days.

The urine marijuana test will give a positive result if the amount of THC in the sample is more than 50 nanograms per milliliter (ng/ml). This is called the cut-off level.

Saliva Tests

Saliva testing is the most common method for roadside testing. For occasional marijuana users, cannabinoids are detectable in the saliva for between one and three days. For heavy users, it is possible to detect THC metabolites for up to 1 month after last use.

Hair Tests

Hair testing is the most sensitive and can detect THC metabolites for up to three months after last use. Trace amounts of THC’s metabolites can remain in the hair for some time. Usually, a 1.5-inch hair segment is asked to provide a window of use over the last three months.

While hair follicle tests can provide information about a person’s cannabis use, they are not always accurate, and the tests often produce false negatives. Hair samples are also prone to contamination, making them difficult to detect with high accuracy. Hair follicle testing is usually used in tandem with urine testing.

Blood Tests

THC and its metabolites are detectable immediately after ingestion or inhalation. For those who have been using large amounts of cannabis regularly, THC metabolites are detectable in the blood for up to one month after last use.

Can You Speed Up the Elimination Process?

Cannabinoids are lipophilic, meaning they bind with lipids and fats in the body, making it difficult to clear the body of their metabolites. Exercise, a healthy diet, plenty of green tea & water, and herbal & vitamin supplements could help rid the body of cannabinoids and their metabolites. Still, it will likely take one to two months to get below the threshold for most people who are regular users.

Regardless of the testing method, cannabinoids can be incredibly difficult, if not impossible, to flush out with over-the-counter products touting the ability to beat your upcoming drug test. Time and patience are one’s greatest allies when attempting to rid their body of cannabis metabolites. The only way you can guarantee testing below the 50 ng/ml cut-off level for cannabis metabolites. 

Frequently Asked Questions

How long does cannabis stay in urine?

Cannabis is generally detectable in urine for up to 30 days, although this window could last longer for regular daily users. 

How long does marijuana stay in your body if it’s your first time?

Marijuana and THC may stay in your body for up to a month, possibly longer, when you smoke it for the first time and subsequent times. The timeframe will depend on numerous individual factors, such as your height, weight, and personal health history. 

Will I fail a drug test if I smoked weed a month ago?

It is possible that you could fail a drug test if you smoked weed a month ago, as marijuana is detectable in blood and urine for up to 30 days. Hair tests are the most likely to reflect if you used marijuana a month ago, as these tests can detect THC for up to three months in some users. However, you may fall below the 50 ng/ml threshold if you don’t consume much.

What about other cannabinoids, like CBD?

Other cannabinoids like CBD are also lipophilic, meaning it is possible to detect them for the same period as THC. However, most standard drug tests do not test for CBD or its metabolites. Instead, they test for THC and its metabolites, like 11-nor-9-carboxy-THC.

This means that, unless you regularly use high amounts of CBD that contain more than the 0.3% limit THC for CBD products, it is unlikely (but still possible) that CBD-only products will result in a positive drug test for cannabis.

Consume cannabis legally and responsibly with a medical marijuana card. The qualified physicians at Leafwell can help you apply online for your MMJ card today. 

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