How Long Does Marijuana Stay In Your System?

Marijuana contains about 500 compounds, including more than 80 cannabinoids, the most potent of which is delta-9-tetrahydrocannabinol (THC). THC is absorbed into the bloodstream and is distributed to different organs such as heart, lungs and brain producing psychological and physical effects ranging from an increased heart rate to paranoia and hallucinations. In the liver, the compound is metabolized to an active (11-OH-THC) that can still produce psychoactive effects and inactive (THC-COOH) metabolite that is stored in the fat and other tissues before finally be excreted from the body mainly in feces and urine.

Inactive metabolites can stay in the system from few days to several weeks after use depending on the quantity consumed, frequency of use, body fat composition and weight of the user as well as the presence of other drugs which can alter body metabolism.

In Urine

Urinalysis is the most common screening test that can detect the presence of marijuana metabolites in your system. The amount and frequency of the consumption are factors that have strong impact on detection time. An increase in both factors will make it harder for the body to eliminate THC and will result in a longer duration of staying it and its sub products in the system. For one time users, for instance, metabolites can be detected from 1 to 6 days following drug intake while in moderate users, it may last up to 7-13 days. In frequent users, the drug remains detectable in the urine for 15 days or more. For heavy users, drug stays even longer in the system thus they may test positive 30 days or more after use.

In Hair

Although drug test using hair samples is less common due to the fact that it cannot detect recent marijuana intake, this test plays a vital role in the field of forensics because it can show positive results for long period of time starting from about 7 to 90 days after use.

In Saliva

Saliva test is conducted mostly for detection of very recent intake of illicit substances. Now it is not very common, but its usage is growing mainly due to testing of drivers on the roads in a lot of countries. Marijuana can usually be detected in saliva during few hours, sometimes up to 24 hours following drug use.

In Blood

THC remains detectable in the blood within few hours, up to 24 hours maximum after smoking. It is an invasive procedure therefore not recommended as the standard preliminary screening test, however it is often done to investigate recent drug consumption during accidents.

In Sweat

Sweat testing is done by collecting the specimen using a sweat patch worn over a period of time or by a more rapid testing device called DrugWipe that can collect samples on-site. Marijuana is detectable in the sweat during a week or up to four weeks after cessation of drug use.