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How long does THC stay in the body?

Come across the statement that marijuana stays in the body much longer than other recreational drugs. So basically, the more THC you take and depending on your weight, it takes longer the longer to clear out. There are as many variations as people out there.

Has anybody tried to test how long does it take? Can you share your parameters? Are there any ways to do it faster?

At minimum for a heavy everyday smoker u r looking at 30 days. It has taken me as much as 6 weeks to clean out for a urine test. A blood test is closer to 6 mos and a hair sample is over a year.

There are so many things that are dependent like the type of test and the amount u smoke.


Here’s some interesting reading :

If I understand the article, THC stays in your hair until you cut it out of there…think haircut. That confirms another article I read in Scientific American a few years ago (sorry, but I can’t locate said article).

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It will continue to show in the root of your hair for up to a year after u quit smoking. The root is what they test.


From the article I just posted :


When you smoke, vape, or eat marijuana, all you’re really doing is facilitating the release of the drug’s active compounds into your bloodstream. Once they’re in your veins, these cannabinoids ride the blood highway to the cannabinoid receptors on the body’s cells, where they bind and exert their effects. Along the way, some of the cannabinoids — metabolites of psychoactive THC are what most tests look for — enter the blood vessels that feed the cells of the scalp. There, at the interface between the vessel and the follicle cells known as the hair papilla, THC jumps the gap, entering the matrix, where actual hair growth occurs. Over the next couple of weeks, the hair from the root sprouts upward, carrying THC past the scalp, where it becomes fair game for testing for the next three months.

hair follicle drug test marijuana

Active compounds from marijuana travel in the bloodstream to a strand of hair via the hair papilla in the hair follicle.Wikimedia


The most commonly cited number for the amount of time marijuana can be detected in your hair is 90 days. That time frame is calculated on the basis of how long it takes for hair at the root to grow past the scalp, and it takes into account the part of the hair that drug testers sample.

According to Quest Diagnostics, one of the premier drug testing labs in the United States, it takes five to 10 days before hair at the root pushes out past the scalp and into the world. In a drug test, samples are usually taken from hair 1.5 inches from the scalp. Since hair grows at about 0.5 inches per month, then you have about 3 months, or 90 days, before you’re in the clear.


A more “scientific” research here :

And an excerpt of that research :


Biological tests of drug use can be used to inform clinical and legal decisions and hold potential to provide evidence for epidemiological studies where self‐reported behaviour may be unavailable or unreliable. We test whether hair can be considered as a reliable marker of cannabis exposure.


Hair samples were collected from 136 subjects who were self‐reported heavy, light or non‐users of cannabis and tested using GC‐MS/MS. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for five cannabinoids (tetrahydrocannabinol [THC], THC‐OH, THC‐COOH, cannabinol and cannabidiol). Samples also were segmented in 1 cm sections representing 1 month exposure and the correlation between amount of cannabinoid detected and self‐reported cannabis consumption tested.


All five cannabinoids were detected. Seventy‐seven percent of heavy users, 39% of light users and 0% of non‐users tested positive for THC. The sensitivity of detection of THC was 0.77 (0.56–0.91) comparing heavy cannabis smokers with light and non‐users, whereas the sensitivity of other cannabinoids generally was considerably lower. The positive and negative predictive value of detection of THC were 0.57 (0.39–0.74) and 0.91 (0.82–0.97), respectively. A correlation of 0.52 (P < 0.001) was observed between self‐reported monthly cannabis use and THC.


In fact yes, marijuana takes some time to disappear from your body. The effects are temporary but three always will be some remains of it until it is processed down by the body. It can take up to 30 days to get rid all of it. But there is an other way, I have read on this blog Marijuana Addiction treatment that there is a way that will get rid of all marijuana that you. I want to use it, when I will use it I will be back with an update. I am really curious about this, I want to know how it will work out.

30 days to clean out liver. Plenty of hydration. Hair will show a decline in usage which is what the courts are looking for. All body hair is usable. So if you shave your head, then hairs coming from another site. You’ll have to shave every inch to hide the hair results.

@stevehayes How much/often do you smoke? That will be the key factor here.

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