The chemical found in marijuana, tetrahydrocannabinol (THC), can stay within a person’s body anywhere from a few days to several weeks depending on many factors. This is not such a great thing when a person is required to submit a drug test. The good news however, is that there are certain steps that you can take to help speed up the process of getting weed out of your system to produce a negative test result.

How marijuana is absorbed in the body?

Tetrahydrocannabinol (THC) is the fundamental psychoactive chemical in marijuana that gives people a high. Once cannabis has been consumed in any way by a person, THC will be absorbed into their bloodstream and will continue to remain in their body after the high has passed. THC is very lipophilic, meaning it is quickly and easily absorbed into adipose tissue (body fat), it is also distributed to the liver, lungs, spleen and vascularised tissues, including the users brain and muscles.

How long does marijuana stay in your system?

The length of time the THC chemical remains detectable in a person’s system is dependent on several factors, therefore will vary between individuals. These factors include:

- The amount of body fat a person has.
- How regularly weed is consumed by the person.
- The amount of cannabis the person has consumed.
- How sensitive the drug test is.

Since THC binds to fat within the body and is stored there, people with higher concentrations of body fat usually metabolise the THC at a slower rate in comparison to someone with less body fat to store it in. If a person consumes weed regularly, or if they have consumed a larger amount, they will have higher THC levels and therefore their body will take longer to reach undetectable THC levels in a drug test. Genetics, gender, age and health issues can also play a part in the length of time cannabis will be present in a person’s system.

Types of Drug Test

The window of detection after consuming marijuana differs greatly between the different drug testing, however, these are an estimate according to each of the main tests:

Saliva Test - Up to 34 hours.
Blood Test - 36 hours.
Urine Test - 1 - 4 days.
Hair Test - Up to 90 days.

The more frequently a person consumes cannabis, the greater the window of detection will be. For example, a saliva test window can reach up to 29 days in a heavy consumer, a blood test, 25 days and a urine test, 30 days. Urine testing is the most common method of testing for THC.

Ways to flush marijuana out of your system

There are several ways a person may be able to speed up the process of flushing the THC from their system before a drug test, these include:

Don’t smoke more weed

Although it should be obvious, the most important factor is not to increase your THC levels any further by consuming more weed until the drug testing has been completed.

Lower body fat

As a longer term solution, since THC attaches to body fat and a higher metabolism will flush THC out more speedily, exercise and maintaining a healthy weight can go a long way in speeding up the flushing process. Be careful not to participate in rigorous exercise too soon before a drug test though, as stored THC can be released from fat cells into the bloodstream, making it much more likely to be detectable in bodily fluids for the test.


Drinking a lot of water on the day of the test may help to dilute urine for a drug test, but this could be suspicious due to the lack of colour a person will produce in their sample. To prevent suspicion, taking vitamins to create a more normal yellow colour will make their urine appear less diluted. Consider taking vitamins B2 and B12 to produce a yellow hue, along with a creatine supplement. The naturally occurring creatine substance will help to make the urine sample appear undiluted also.

Most importantly, being dehydrated will increase the level of THC detected in a person’s body, so even if they are not drinking for the purpose to dilute, drink water to prevent being dehydrated.

THC Detox

A person can detox on their own with a healthy diet, exercise and plenty of water prior to taking a drug test or with the aid of detox drinks, tablets and kits. Not all detox aids are created equally, so be sure to do some research on which one will be most suitable for a person’s particular needs.


Taking zinc supplements to falsely pass a urine drug test by adulterating the sample is another option to use for a drug test. A 2011 study supports the belief that zinc helps in masking the presence of THC found in urine.

Herbal Supplements

Some herbal supplements that will help with the detoxification process include; milk thistle, cayenne and psyllium seeds. Green teas and herbal teas have antioxidants and can assist with detoxification too, however, as good as these supplements may be for your body, they will most likely not speed up the flushing process alone.

Activated Charcoal

Activated charcoal is a porous form of carbon that attracts fatty compounds within bile once inside the intestinal tract. Bile is a digestive liquid created in the liver and stored and released by the gallbladder, it aids the body in breaking down fat. Since a large amount of the THC metabolites that are excreted by the body are done so via bile, activated charcoal could be helpful in flushing THC due to being able to attract bile.

Sauna - sweat it out

Although spending time in a sauna is not likely to have a big impact in lowering your THC levels, sweat can have traces of THC present for up to a week after consuming marijuana if a person is a heavy consumer. It can be a beneficial addition to a person’s detox plan, as long as they remain hydrated.

Final Thought

The thought of having a drug test can be daunting, especially since there is no perfect equation that will be able to predict the amount of time that THC will be undetectable after consuming marijuana. By taking steps to be in the best position possible both before and after consumption is the best way to get THC out of your system as quickly as possible to pass a marijuana drug test.

Disclaimer: The information provided is intended to be a helpful guide to flushing THC from a person’s system. Ensure you always seek advice from a medical professional before any big lifestyle changes.