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  • Christopher D.

How Long Does Marijuana Stay in Your System?

Marijuana, also known as cannabis, is a widely used drug that is gaining increased legality worldwide. A common question that arises from the use of weed is the duration it remains in the body.

The answer to this inquiry is not as simple as expected because various factors can influence how long marijuana stays in the system. In this article, we will discuss the effects of weed on the body, the factors that can impact its duration in the system, and how long it can be detected in different body fluids and tissues.

This information will provide readers with a better understanding of the potential risks of marijuana use, the importance of moderation, and the need to be mindful of the implications of drug testing.

Understanding the Effects of Marijuana on the Body

Weed, or marijuana, is a plant that contains a group of compounds known as cannabinoids, which interact with the body's endocannabinoid system.

The most well-known cannabinoid is delta-9-tetrahydrocannabinol (THC), which is responsible for the psychoactive effects of weed. When weed is smoked, THC is rapidly absorbed into the bloodstream and travels to the brain, where it binds to cannabinoid receptors and produces its effects.

Apart from producing a high, weed can also cause a range of effects on the body, such as increased heart rate, impaired cognitive function, and dry mouth. However, the duration and intensity of these effects can vary depending on several factors.

Factors That Impact How Long THC Remains in Your System

The length of time that weed remains detectable in your system is influenced by various factors, including:

Frequency of use:

People who use weed regularly are more likely to have higher levels of THC in their system for longer periods of time.

Method of use:

The method of consuming weed, such as smoking, vaping, or consuming edibles, can influence how long THC remains detectable in your system.


Higher doses of THC are more likely to produce detectable levels of the drug in the body for longer periods of time.


The rate at which your body breaks down THC can vary depending on factors like age, gender, and general health.

Body fat percentage:

THC is fat-soluble, which means that it can accumulate in fat cells in the body. Individuals with higher body fat percentages may have detectable levels of THC in their system for more extended periods.

How Long Can THC be Traced in Blood?

THC, the main psychoactive cannabinoid in weed, can usually be detected in blood for a short period, ranging from a few hours to a few days after use.

Nevertheless, heavy users or people who consume high doses of THC may have a longer detection window. Blood tests are commonly used to identify recent drug use, particularly in cases of driving under the influence.

These tests detect the active THC compound in the bloodstream, making them a reliable indicator of recent marijuana use. However, it's important to note that the detection window for blood tests is relatively short compared to other drug tests, such as urine or hair tests.

In some cases, THC may only be detectable in blood for a matter of hours, making it difficult to detect marijuana use after the initial effects have worn off.

The Length of Time Marijuana Can be Detected in Urine

Marijuana can be detected in urine for a longer period of time than in blood, making it a common method for drug testing.

THC is typically detectable in urine for up to 30 days after use for heavy users, while occasional users may have detectable levels for only a few days after use. The length of time THC remains in urine can also vary based on several factors, such as the method of use, dosage, and the individual's metabolism.

Urine drug tests are commonly used by employers, schools, and other institutions to detect drug use and ensure compliance with drug-free policies. It's important to note that while a positive urine test can indicate recent marijuana use, it does not necessarily mean that the individual was impaired at the time of testing.

How Long Can THC Be Detected in Hair?

Marijuana use can be detected in hair for the longest period compared to blood and urine, lasting up to 90 days after use. This is because THC metabolites from marijuana are stored in hair follicles and remain in the hair as it grows.

While hair tests are less common than blood or urine tests, they are a preferred option when detecting long-term drug use. Unlike blood and urine tests, hair tests can show a history of drug use over several months.

It's worth noting that hair tests are more sensitive to traces of THC, so they may produce positive results even if the individual has not used marijuana for several months. Additionally, hair treatments like bleaching or coloring do not remove drug metabolites from the hair, as they are embedded in the hair shaft.

How Long Does Marijuana Stay in Saliva?

Several factors impact how long marijuana stays detectable in saliva, including the frequency and amount of use, the potency of the marijuana, and metabolic differences between individuals.

Saliva tests can detect THC for up to 72 hours after last use, but this window can be longer for frequent or heavy users, lasting up to a week or more. Saliva tests are commonly used in roadside drug tests, and can detect marijuana use within hours of last use, making it a more immediate method of detection compared to blood or urine tests.

Get Your Medical Marijuana Card Today!

Medical marijuana is legal in the State of Louisiana, and you can get your medical marijuana card today! It is now easier than ever to get your card, so if you think cannabis may benefit you, what are you waiting for?

If you aren’t sure if you qualify for a card, we can help! Just give us a call and we can answer any questions you may have.

Marijuana is an excellent alternative medicine that offers natural, safe, and legal relief for an array of symptoms. If you think cannabis could help some of your symptoms, what are you waiting for?

Schedule an evaluation online today with one of our knowledgeable, compassionate doctors to see if you qualify for your medical card. Not only will you discuss your condition and options, but you can do so through a virtual appointment in the safety of your own home!


Doctors Who Care.

Relief You Can Trust.

At Louisiana Marijuana Card, our mission is helping everyone achieve wellness safely and conveniently through increased access to medical marijuana. Our focus on education, inclusion, and acceptance will reduce the stigma for our patients by providing equal access to timely information and compassionate care.

Call us at (833) 253-2943, or simply book a medical marijuana evaluation to start getting relief you can trust today!


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