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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.

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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.

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From the article I just posted :

HOW DOES WEED GET IN MY HAIR, ANYWAY?

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

HOW LONG DOES IT STAY THERE?

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.

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A more “scientific” research here :

And an excerpt of that research :

introduction

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.

Methods

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.

Results

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.

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