How Long Does THC Stay In Your System When You Consume Marijuana?

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"Neither being unemployed nor applying for unemployment insurance is, by itself, a legally sufficient reason under the Constitution to subject a citizen to government-operated drug testing. " - National Employment Law Project

How Long Will Marijuana Stay In My System?

I was once counter-sued by a former business partner for my public opposition to mandatory marijuana drug testing by a prominent marijuana company. That’s a fact that I’m actually very proud of. The whole ordeal resulted in a positive resolution by the marijuana company, which with the help of activists, came up with an impairment based drug testing policy that didn’t arbitrarily require employees to turn over their urine or be not-hired/fired.

My public opposition led to me being counter-sued in court because it allegedly resulted in a lost advertising deal with the company at the time, but unlike the person that tried to take action against me in court, I don’t feel that any amount of money is worth compromising one of the most basic principles of the activism movement. Drug testing companies have always led the fight against reform, and siding is just something I can’t stomach. I couldn’t at the time, and can’t now. I will never support arbitrary drug testing in any industry, especially the marijuana industry.

I think we can all agree that impaired (from any substance) employees shouldn’t be working with volatile chemicals at an extraction facility. But I think we can also all agree that just because someone has marijuana in their system, that doesn’t necessarily mean that they are impaired. Marijuana remains in a person’s system for a very long time in some cases. It depends on a lot of factors – frequency of use, the amount of body fat a person has, what their metabolism rate is, what the person’s diet is like, how much stress they deal with, etc.

It’s necessary to discuss the difference between marijuana being in a person’s system and whether or not a person’s marijuana consumption will result in a failed drug test. Marijuana can technically remain in a person’s system for as long as 100 days. That’s not the case for most people, but for a heavy user that has a lot of body fat and a slow metabolism, it can certainly happen. But just because a person has marijuana in their system doesn’t mean they will fail a urine-based drug test, which is the most commonly administered form of drug test.

Leaf Science has a great explanation for what a drug test is specifically looking for:

THC is the active ingredient in marijuana and the chemical responsible for the high. However, urine tests detect a different chemical called THC-COOH.

THC-COOH is a metabolite of THC. It is produced when the liver breaks down THC and stays in the body for much longer.

Again, just because a person has a detectable amount of THC-COOH does not mean that they will fail a drug test. Most drug tests that people take for a job or for criminal justice related reasons have a threshold of 50 ng/mL. A person could consume marijuana and be above the limit for a couple of days following use, but then fall below the threshold.

That exact scenario happened to my friend who was working for a company that sprung a random urine test on him the first working day following New Year’s (perhaps timely info for today!?). My friend didn’t consume very often, but did so on New Year’s Eve. He only had a few puffs from a joint, but he was sweating bullets when he had to go ‘fill the cup’ a few days later when he returned to work. He had a detectable amount in his system, but was below the threshold of 50 ng/mL. Fortunately my friend got to keep his job, but a guy in his similar situation didn’t pass the test and was fired.

The fact of the matter is that there is no ‘one-size-fits-all’ answer to the question ‘how long does THC stay in your system when you consume marijuana?’ There are just too many factors at play, as pointed out by Dr. Alan Shackelford in an article from The Cannabist:

“Unfortunately, there is no short or easy answer to that question. The cannabinoids are fat-soluble and are stored in body fat and released from there over time, so whether they show up on drug testing (which I assume is the actual question) depends on many factors, including how much cannabis has been used over what period of time, how much body fat someone has, exercise patterns, diet and others.”

That line of thought was echoed by Ryan Vandrey, an associate professor of psychiatry and behavioral science at Johns Hopkins University, in an article from Leafly:

“There is no typical window of detection,” says Ryan Vandrey, an associate professor of psychiatry and behavioral science at Johns Hopkins University. “It is highly variable from person to person and it varies based on the frequency of use and the amount of use. So there is no way of predicting or knowing how long someone would test positive with any kind of certainty.”

I have a good friend that was forced into rehab after his work detected marijuana in his system. He was posed with the choice of going to rehab, or being terminated from the job he loved and had worked so hard to get into. He reluctantly chose rehab. I will never forget how many sessions we had leading up to his 12 week stint. We puffed like there was no tomorrow. My friend, who was fairly chubby, of average height, and in his mid 20’s, said that it took him six weeks to get below the 50 ng/mL limit, for what that’s worth.

If you consume marijuana and have a urine-based drug test coming up, I’d imagine you are scrambling to see what you can do to pass the test. You have probably heard of many anecdotal tips and tricks. Paul Armentano, Deputy Director of NORML, has been quoted as saying that there are only two known studies out there that which back up methods for helping marijuana consumers pass a drug test.

The first one involves zinc supplements, which if taken orally, seems to be able to interfere with the detection of the metabolites that drug tests look for. The ‘masking effect’ lasts about 12-18 hours. The second scientific study involves papain. Researchers concluded at the end of the trial that there was a ‘direct pH, temperature, and time-dependent correlate between the increase in papain concentration and the decrease in THC-COOH concentration.’

But even those studies come with a big asterisk, in that how much the zinc supplements will mask the marijuana in your system, or how much the papain decreases your THC-COOH concentration, is dependent on the same factors previously described for how long marijuana stays in a person’s system.

Johnny Green
About Johnny Green 662 Articles
Johnny Green is a cannabis activist from Oregon. Johnny has a bachelor's degree in public policy, and believes that the message should always be more important than the messenger. #LegalizeIt #FreeThePlant