How Long Does Weed Stay in Your System?

Weed can remain in your system for between 3 and 90 days, depending on the frequency of use and other factors. Drug tests can detect weed in your urine, blood, saliva, and hair, although each has a different detection window.  

Weed, or marijuana, which comes from the cannabis plant, is unlike many other drugs, which tend to exit the system more quickly. This can cause difficulties when you need to pass a drug test, whether you are part of a sports team, an employee, or part of other organizations that test and enforce substance abuse policies.

How long weed stays in your system depends on many factors, making it difficult to predict the exact detection time of the drug. However, this article can help you estimate how long weed stays in urine, blood, saliva, and hair, as explained by Avenues Recovery, a leader in addiction detox and rehab.

What Are THC and CBD?

THC (tetrahydrocannabinol) and CBD (cannabidiol) are both compounds found in cannabis plants. THC is the psychoactive component that creates the ‘high,’ while CBD is non-psychoactive and is often used for its potential therapeutic benefits.

Each time a person uses cannabis, whether through smoking or ingesting, THC and many other chemicals enter into their system. Although many other plants contain THC, it is mostly associated with weed as its primary compound. 

Many people confuse THC with CBD, and although similar, they have quite a few differences. They both have a similar composition and contain 21 carbon particles, 30 hydrogen particles, and two oxygen particles. However, THC and CBD are organized completely differently. The difference in their chemical structures changes how they affect your body when you smoke or ingest a drug containing them.

Both CBD and THC work with the receptors that discharge neurotransmitters in a person’s head, leading them to influence things like mood and memory. The main difference between them is that THC causes a ‘high’, but CBD does not.

CBD is derived from the hemp plant, a close relative of the marijuana plant, and can be beneficial in its use. It is most commonly found in oil form, but it’s also sold as a liquid, extract, and capsule. CBD doesn't contain tetrahydrocannabinol (THC), so it doesn’t induce any mind-altering effects. Instead, it helps with various aspects of the body and can promote physical health. It is often used in over-the-counter drugs and medications. 

Where Is THC Metabolized?

THC is primarily metabolized in the liver, where it is broken down by enzymes into various metabolites, including the more potent 11-hydroxy-THC.

When weed is smoked, the THC and other chemicals directly enter the lungs and are absorbed within seconds. This is because our lungs are fixed with many alveoli, the minuscule air sacs where gas exchange happens. These alveoli have a large surface area, making it simple for THC and different substances to enter the body. The THC then travels through the bloodstream to reach the liver.

THC is also used in vapes as an alternative to smoking as it does not burn the cannabis. Vaped marijuana and smoked marijuana enter the body in the same manner.

Ingesting marijuana, however, delivers the THC straight to the blood through the digestive system, where it eventually reaches the liver for metabolism.

Regardless of how weed is administered, it binds to receptors and blocks the neurotransmitters, causing that euphoric, high feeling.

How Long Does THC Stay In Your Body?

THC stays in your body for 2 to 90 days due to its long half-life, depending on the testing method. The half-life of a drug is the time it takes for the concentration of the substance in the body to reduce by half.

What Is the THC Half-Life?

The THC half-life depends on the frequency of marijuana use, with studies showing it to be 1.3 days in an infrequent user and 5-13 days in a frequent user.

How Long Does Weed Stay In Your System for Drug Testing?

How long a drug test can detect weed depends on factors like frequency of use and metabolism. The types of drug tests available include urine tests, blood tests, saliva tests, and hair tests. Each method has different sensitivity and time frames for detecting THC and its metabolites.

How Long Does Weed Stay In Urine?

The THC chemical found in weed can be detected in urine for 3 to 30 days, depending on the frequency of use: 

• Single-use: detectable for 3 days after use
• Moderate use (several times a week): detectable for 5 to 7 days after use
• Chronic use (multiple times daily): detectable for 30 days or more after use

Often, THC detection times can be even longer. Urine testing is the most common form of drug testing because it’s simple, quick, and painless.

How Long Does Weed Stay In Your Blood?

THC can be detected in blood for two days from just seconds after it is inhaled. A blood test is a far less common drug testing method than urine testing, as it can sometimes only gather results from the previous few hours in infrequent users. 

How Long Does Weed Stay In Saliva?

The THC chemical found in weed lasts in your saliva for 1 to 2 days after last use for occasional users and 2 to 3 days for chronic users. A saliva test can be conducted when the person has inhaled marijuana smoke or has been exposed to it. It is often used by police forces in roadside testing. 

How Long Does Weed Stay In Your Hair?

Small blood vessels allow the weed to reach the hair follicles, and THC can be detected in hair for 90 days after usage. A hair test is the least common drug testing method, as it is a little more complicated than urine, blood, and saliva tests.

Weed in System Chart

How Quickly Does Marijuana Start Working?

Once marijuana enters the system, it can take between 2 to 10 minutes to feel the effects when the marijuana is smoked, and 30 to 60 minutes when ingested. In some instances, it can even take as long as 3 hours.

How Long Do the Effects of Weed Last?

When smoked, the effects of THC peak after about 10 minutes and can remain for the next 1 to 3 hours, sometimes lingering even 8 hours after usage. When marijuana is ingested, the THC effects peak after about 2 hours and may remain for about 24 hours.

The duration of the effects varies between individuals and depends on several factors:

• THC levels within the body
• Amount consumed
• Body weight and fat percentage
• Metabolism
• Whether food was consumed beforehand
• Personal tolerance

How Long Does Weed Stay In the System After Quitting?

THC generally stays in the body and can be detected for 2 to 30 days, depending on many factors, including:

• Frequency of use 

• The type of test being administered

• Body fat

• Dose taken 

• Sensitivity of the test

Frequent vs. Occasional Use of Marijuana

Frequent users of marijuana are more likely to fail drug tests than infrequent users. This is because THC can remain in a daily user’s system for up to 90 days after their last use, showing up in a hair test. Drug tests can detect the smallest amounts of THC in the system. Even with detection estimates for each type of testing, there are always uncommon cases where THC can be detected after even longer periods.

How to Get THC Out of Your System

To get THC out of your system, the first step is to stop using weed. Then, you can try staying hydrated, exercising regularly, and maintaining a healthy diet to speed up the natural detox process.

• Stop Using Marijuana: Allow your body time to metabolize and eliminate THC naturally.
• Hydrate: Drink plenty of water to help flush out THC metabolites.
• Exercise Regularly: Exercise boosts your metabolism and helps to burn fat cells where THC is stored.
• Healthy Diet: Maintain a balanced diet and avoid fatty foods to support weed detoxification.
• Detox Kits: Some detox kits claim to speed up the process. However, their effectiveness can vary and should be used with caution.

Remember, there are no guaranteed quick fixes, and the best method is to give your body time to cleanse itself.

Quality Treatment for Getting Weed Out of Your System 

Marijuana is a very addictive substance that can have numerous detrimental effects on your life. Aside from the health issues it can cause, the long half-life of THC means that marijuana stays in your system for long periods after use, increasing the risk of failing drug tests. Whether you live in a weed-legal state or not, this can cause issues for many people.

There are many treatment options available, including medical detox and residential rehab, that can help you get your addiction-free life back. The experienced and compassionate addiction counselors at Avenues Recovery are ready to help you and answer any questions you have about addiction. Don’t hesitate to reach out today!

FAQs About Drug Testing for Weed

How long can a drug test detect weed? 

The detection times for weed vary by test type: urine (up to 30 days), blood (up to 2 days), saliva (up to 3 days), and hair (up to 90 days). Factors like frequency of use and metabolism also affect detection.

How long does weed take to leave the system? 

The THC chemical in weed generally stays in the body for 2 to 30 days, depending on factors such as frequency of use, metabolism, and body fat. It can be detected longer in hair (up to 90 days).

How to pass a drug test for weed? 

The best way to pass a drug test for weed is to stop using marijuana as early as possible before a drug test and give your body as much time as possible to detox naturally. However, if you’re facing a drug test soon and don't have sufficient time for your body to clear the THC, you should be aware of the risks involved in trying to cheat the test. Methods like drinking excessive amounts of water, using detox products, or submitting someone else's urine can be risky, leading to invalid or suspicious results, which may raise red flags.