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In general marijuana can stay in your system for weeks or longer. Reports have shown that the substance can remain detectable for up to 90 days, even when the “high” or the calming effects have disappeared.

THC stands for Tetrahydrocannabinol. THC is the chemical in weed that gives the feeling of “high” to people. Some factors that can affect how long THC stays in blood and urine include:

  • The level of body fat someone has
  • The intensity of consuming the THC
  • The method of the drug test

Compared to alcohol, THC will need much longer to completely disappear from your body. THC is categorized as a lipid-soluble chemical. This causes THC to bind to body fat. Therefore, it will be harder for THC to disappear. 

How Long Does Weed Stay in Your Saliva?

According to research, THC can remain in your saliva for 24 to 72 hour in the case of infrequent users. On the other hand, it can remain for up to 30 days in the saliva of frequent users.

Another study showed that THC can remain in saliva for a maximum of eight days for regular users. According to the study, THC levels in urine were not consistent with that of saliva as they kept reducing over time.

Another research was done to determine the level of THC and other cannabinoids in occasional and frequent users. In the study, the saliva of the participants were tested 19 hours before smoking weed and after smoking.

The researchers tested them after a regular interval of 30 hours. After 13.5 hours, all participants tested positive for THC. According to this study, THC needs a minimum range time of 13.5 hours to be removed from saliva. 

Saliva Swab Test

The saliva swab test is usually used to conduct drug tests in unplanned places, such as on a roadside. This is due to the ease in carrying out this test. Each region may have different rules regarding the threshold for the substance.

However, adhering to the guidelines from the Substance Abuse and Mental Health Services Administration, the threshold for THC is 4 nanograms per milliliter. The saliva swab test detects the presence of the Δ9-THC. the Δ9-THC is the molecule found in cannabis and it binds to your saliva. The amount of the Δ9-THC molecule identified in the saliva will be significantly higher if the user smokes the marijuana.

The test will show a positive result of marijuana usage if the person tested has a pure Δ9-THC concentration in the saliva higher than 10 nanograms per milliliter of saliva. Saliva swab tests, with new technologies, offer instant answers with minimally invasive attempts. It only needs 10 minutes to show the result. This is why it is chosen as a practical marijuana test.

Unfortunately, the saliva swab test has some concerning issues regarding the precision of the test. This test was created as a practical and efficient screening test. The test will only be able to identify how much THC is left in your saliva. That means there are many factors affecting the amount of it and the results will vary between people.

Unlike in other test methods which try to detect any signs of THC in your metabolism, saliva swab test will only detect any presence of the substance left in your saliva. This test will only be able to detect the substance 24 hours after use. Beyond from that time period, the test will not detect any THC presence. 

Other Marijuana Test methods

Besides using saliva, some drug tests procedures can be used to detect any presence of THC in your blood and urine.

How Long Does THC Stay in Blood?

When consumed, especially if smoked or vaporized, THC goes into your bloodstream through your lungs. THC can stay detectable in your blood 3 to 4 hours after use.

How Long Does THC stay in Urine?

Urine tests have a longer detection period. THC can stay in your urine for up to 30 days. However, it depends on many factors like metabolism and hydration. But, it can stay detectable in your hair for up to 90 days after use.

Many factors will also play a role. Sex, for example. THC will possibly linger for a longer time in a female body compared to the male one because females have more body fat concentration.

How to Pass the Saliva Swab Test

If you are have an upcoming drug test from any authorities, please be concerned about the time period from your last marijuana use. You can take the data above as a reference. Do not use marijuana and drive, spare at least a 24-hour time period, especially if you want to avoid failing the saliva swab test.

Some users have provided some tips on passing the saliva swab test. Some say that cleaning your mouth thoroughly by flossing, brushing, and rinsing repeatedly can help greatly flush out the THC.

Antiseptics is reported to be effective in altering the content of your saliva. Yet, this method will only be effective for approximately 30 minutes. Thus, you need to do it as close as possible to the test.

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To sum it up, there’s no possible way to know exactly how much time you need to eliminate any THC trace from your body. Too many factors play roles here but you can do certain things to help the process. However, please make sure that you use marijuana safely and legally.

Karen Getchell, expert cannabis writer
Karen Getchell

Karen gained expertise in developing training programs and technical documentation as a Senior Editor at Cisco Systems. She began her journey in cannabis as a patient, searching for a way to heal herself. When she perfected a method for making cannabis oil, other patients began to seek her out. An early adopter of CBD medicine, she started her CBD-infused-products business in 2014. Over the last two decades, Karen has taught hundreds of patients and caregivers how to select strains, infuse oils, and extract cannabinoids.

When she isn’t teaching cannabis cooking classes, Karen works as a cannabis business consultant, writes for online cannabis publications like Cannabis Training University, Leafly, and Weedmaps, and runs a CBD-infused-product business.

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