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Cannabis/Marijuana (THC) detection time

Cannabis/Marijuana (THC) detection time


How long does marijuana remain detectable (in urine, saliva, hair)? Discover in this article all the essential information about the detection time of cannabis in the different body matrices.

With a cannabis urine test

Depending on the frequency of use, the detection time will generally be:
  • Occasional users: 2 to 3 days.
    Smoking one or two joints on an exceptional basis leaves traces for only a short time.

  • Regular users: 5 to 10 days.
    Smoking several joints a month, or even a week, leaves traces over a much longer period of time.

  • Chronic users: 14 to 60 days or more.
    Very heavy cannabis use will leave persistent traces over a very long period. We're talking here about consumption of 1 to several joints a day.

Why do traces of cannabis remain in the system for so long?

Quite simply because the human body stores THC (the active ingredient in cannabis), since it can only eliminate it relatively slowly. THC naturally binds to certain body tissues, notably fat. The higher the level of consumption, the more the body will store THC until it can be eliminated. This is why regular or chronic cannabis users will remain positive to the urine test for several weeks after the last joint smoked.

Please note that these detection times are indicative, and will differ according to individual metabolism. We are not all equal when it comes to drugs and their effects. For the same level of consumption, some people will store THC longer than others.

The test shown here is the NarocCheck® PreDosage®, which detects cannabis on 3 levels.

  • Level 1 : LOW (urine slightly positive for THC)
  • Level 2 : MEDIUM (urine significantly positive for THC)
  • Level 3 : HIGH (urine strongly positive for THC)

With a cannabis saliva test

The level of consumption will not have a major influence on the time it takes to detect cannabis in saliva. Several scientific studies have shown that THC levels in the mouth drop drastically 4 to 6 hours after the last joint smoked, to a level far too low to be detected with a saliva test.

That said, it's obvious that several joints smoked over a fairly short period of time can extend this detection time by an hour or more.

Why is the detection time shorter than with a urine test?

Because traces of cannabis do not circulate in saliva. The only THC that can be detected in the oral cavity is the THC deposited there during consumption of a cannabis cigarette. However, these traces cannot remain for long in such a biological environment, as the mouth is constantly "cleaned" by fresh saliva. Detection time is therefore necessarily limited.

With a cannabis hair test

Hair is a true listing of the substances to which an individual has been exposed. Whether it's heavy metals, drugs or narcotics, hair retains traces of these exposures.

There is currently no rapid hair screening test, but laboratory screening is now available to private individuals. They are performed using a chromatographic technique coupled with mass spectrometry, giving them a reliability level of over 99.9%.

Extremely reliable and totally anonymous, hair tests are available in several versions: single-drug and multi-drugs.

Founder and manager of Kappa City Biotech since 2005.
Through the blog DrugNews, I share my experience on how to deal with situations related to drug and alcohol use, whether in the family sphere or in the workplace.