THC is detectable for only a relatively short period, but the cannabinoid’s metabolites can stay around in the body for much longer.
While the euphoric effects of THC can fade rather quickly, the compound and its metabolites can stay in your system for weeks after consumption, in some cases even longer.
THC, or tetrahydrocannabinol, is the active compound found in medical marijuana that causes short-term euphoric effects.
Depending on where you live and your place of employment, you may have concerns about how long THC stays in your system. Marijuana and THC are illegal under federal law, and laws regarding marijuana use for medical or recreational purposes vary depending on your state. Some employers and athletic organizations, even in states where marijuana is legal in some capacity, can also impose restrictions on THC consumption.
So how long does THC stay in your system? Unfortunately, there is no simple answer.
How THC Affects Your System
When you consume medical marijuana, THC levels in the bloodstream temporarily rise. Your blood carries THC to the brain and other organs throughout the body, where the compounds interact with cannabinoid receptors and cause short-term euphoric effects.
THC stimulates neurons in the brain’s reward system to release the signaling chemical dopamine and elicit the pleasurable “high” associated with marijuana. Euphoric feelings associated with THC include an altered physical sense and perception of time, changes in mood, feelings of creativity and relaxation, and impaired body movement.
When medical marijuana is smoked or vaped, these short-term effects manifest within seconds and become fully apparent within a few minutes. Depending on your metabolism and the potency of the product consumed, these effects typically last for 1-3 hours. When medical marijuana is ingested, like in the case of marijuana edibles, the onset of effects is delayed by digestion and takes hold in about 30 minutes to 2 hours after consumption. The duration of effects when THC is ingested is prolonged because of continued slow absorption.
THC itself is only detectable in the bloodstream for a short period. After a few hours, THC is rapidly broken down and modified into at least 80 different metabolic byproducts. While THC levels drop significantly after a few days, the use of cannabis and THC consumption can be detectable in other ways even afterward.
THC and its metabolic byproducts, called metabolites, are lipid-soluble. This means they accumulate in fat reserves throughout the body and then are slowly released over time. Eventually, the metabolites are eliminated from the body through feces and urine.
How Long THC is Detectable
While the euphoric effects of THC last for only a short period, the compound’s byproducts, or metabolites, linger in your system for much longer.
When considering how long the byproducts of THC stays in your system, it’s important to understand that it can depend on which system is being discussed.
In the bloodstream, THC is rapidly metabolized by your body and typically remains detectable for a few hours to 1-2 days after a single use. In daily consumers or among those who consume cannabis multiple times per day, THC may stay in the bloodstream for up to a week after the last session.
In the saliva, THC remains until it is swallowed fully, which typically takes about one to two days. Drinking water, brushing your teeth, eating fatty foods, and using mouthwash can help remove THC from saliva faster.
In the urine, byproducts of THC are detectable for a longer period of time. While the detectable window can vary, research suggests that in general THC byproducts remain for 5-8 days after one time use, 11-18 days when cannabis is consumed 2-4 days per week, 33-48 days when consumed 5-6 days per week, and around 50-65 days if cannabis is consumed daily.
THC metabolites stay in your hair for longer than any other system in the body. While most hair tests look for evidence of cannabis use over the last 90 days, some hair follicle tests can reveal marijuana use for up to a couple years.
A 2005 research review from researchers at the Toxicology and Drug Monitoring Laboratory at University of Missouri found that THC detection can exceed 30 days in some people, but it is a rare occurrence.
Factors That May Impact THC Metabolism
Each of us has a unique metabolism that processes THC at a different rate. Even among people of the same gender and age, individual lifestyle choices, body makeup, and cannabis consumption habits can influence how quickly the body eliminates THC.
Some factors that can impact the rate of THC metabolism include:
- Eating habits
- Levels of exercise activity
- Metabolic rate
- Body fat content
- THC potency of cannabis
- Frequency of cannabis consumption
Because of these variables, it is nearly impossible to predict or know how long THC will remain detectable in a person with any kind of certainty.
THC and Drug Testing
Many people concerned about how long THC stays in their system are curious because they’re going to be subject to a drug test, perhaps at random at their place of employment, by a potential new employer, or as part of their athletic competition requirements. Even in states where recreational or medical marijuana are legal, employers can and do restrict employees from using cannabis.
There are many different kinds of drug tests available, with each varying in levels of sensitivity and time periods to detect cannabis. An employer or athletic organization may use urine, hair, blood, saliva, breath, sweat, and even fingernails to investigate whether a person has recently consumed marijuana.
Urine analysis is by far the most common type of drug test used by employers. The test can be conducted at your workplace using a test strip, or a sample may be sent away to a third-party laboratory for analysis. A urine test for marijuana does not look for THC. Rather, it’s able to detect the non-psychoactive metabolite 11-nor-delta9-caboxy-THC (THC-COOH).
Several factors can influence whether THC will be detectable in a drug test, including a person’s unique biology and patterns of cannabis usage.
This means there is not really a typical window of detection regarding a urine test that applies to everyone. Whether THC will be detected in a drug test is highly variable for person to person and it depends on the frequency and amount of use. In general, THC-COOH can linger in urine for days or weeks.
Ways to Get THC Out of Your System
While there are some methods you can use to help manage the temporary euphoric effects of THC if you accidentally consume too much, speeding up the process of flushing out THC metabolites from your body’s systems can be difficult.
There are a couple of techniques that may help flush THC out of some of your systems.
For example, reducing calorie intake, exercising, and consuming high amounts of water may help flush THC from the body’s fat cells. Drinking water can also help reduce the concentration of THC metabolites in the urine.
The only method for ensuring that you’ll pass a drug test, however, is to abstain from medical marijuana consumption.
More on Medical Marijuana
You can learn more about medical marijuana, including information on how to obtain it legally or grow cannabis on your own at home, by visiting our Cannabis 101 page. Keep up with the cannabis-related legislative and industry developments through our news page.