The amount of time that your body retains traces of marijuana depends on a number of factors, including how often you smoke and your metabolism rate.
Urine testing, or urinalysis, is the most common way of screening for marijuana use. In the United States, current and future employers will often ask you to undergo a urine test.
But how long will marijuana show up in your urine after you stop smoking? Unfortunately, the only accurate answer is: It depends.
THC vs. THC-COOH
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.
The most common cutoff level for THC-COOH used by drug screening companies is 50 ng/mL. Less common cutoff levels are 20 ng/mL and 100 ng/mL.
Length of Detection Period
No one can really say how long you will test positive for marijuana, since the rate of THC metabolism varies per individual. The amount of marijuana consumed can also alter the window of time that your body retains traces of THC.
Even still, studies provide some insight into how long the average individual will test positive for marijuana.
Someone who smokes occasionally — or for the first time — will likely test positive for 1-3 days afterward, according to a review by the National Drug Court Institute (NDCI).
But by the end of 4 days, infrequent cannabis users should be safely below the 50 ng/mL threshold.
“For occasional marijuana use (or single event usage), at the 50 ng/mL cutoff level, it would be unusual for the detection of cannabinoids in urine to extend beyond 3-4 days following the smoking episode.”
Studies suggest someone who smokes often can expect to test positive for around a week following last use. According to the NDCI, after 10 days, most frequent users should pass a urine test at the 50 ng/mL threshold.
“Based upon recent scientific evidence, at the 50 ng/mL cutoff concentration for the detection of cannabinoids in urine, it would be unlikely for a chronic user to produce a positive urine drug test result for longer than 10 days after the last smoking episode.”
However, there’s no guarantee that a heavy cannabis smoker will be free of THC metabolites after 10 days. Studies show it’s possible for some users to test positive for up to a month after last use.
In one extreme case, a person who reported using cannabis heavily for over 10 years managed to test positive (above 20 ng/mL limit) for up to 67 days after last use.
How To Pass A Urine Test
While there are a number of products being marketed as urine cleansers, there is probably good reason to be skeptical of their claims.
Drinking an excessive amount of liquid may be the most scientific solution, since it would naturally dilute anything found in your urine.
But drinking too much water could spoil the sample. Urine that is too diluted may be identified and rejected by the testing lab as possibly being tampered with. Still, this could buy some time for a retest, depending on the circumstances.
If you have to take a urine screen for employment or other purposes then we highly recommend you do a full detox and not attempt to "cheat" the test. Although how long it takes is different for everyone, eventually your body will remove THC from you system through its natural processes. That being said, there are ways to boost you body’s excretion systems (urination, feces and sweating) and speed up THC removal. If you have at least three weeks until your drug screen and are a fairly healthy person that isn’t a very heavy smoker, then we’re confident you can detox naturally and pass your test by following the below:
1. Abstain from inhaling or ingesting marijuana – Obvious enough.
2. Eat a clean diet that is low in carbohydrates and sugar - A diet like this forces the body to metabolize fat (where THC metabolites are stored) instead of glucose.
3. Drink lots of water and green tea - Having healthy amounts of both water and green tea will lower THC metabolite levels through their diuretic properties and cleansing of the kidneys. Additionally, hydration is a key factor for a robust metabolism.
4. Exercise and hit the sauna, steam-room or jacuzzi – All of these will speed up a person’s metabolic rate, burn THC metabolites and stimulate waste removal.
Natural Detox Kits
If you have less than two weeks until your THC urinalysis or are simply looking for additional assurance that you’ll pass, we recommend obtaining a natural ingredient detox kit. These natural kits are typically safer than many of the harsh masking agents on the market. Additionally, if you only have a short amount of time, detox kits that truly remove detectable THC metabolites from your system can be the missing link between your body’s excretion systems and passing your test. One of the natural detox kits that we recommend is Verdant Herbal's 48 Hour THC Detox Kit. Verdant Herbal's detox kit is a unique THC cleanse that has evolved over the past 8 years using customer research, feedback and independent studies done within the industry. They have isolated the most effective ingredients and brought them all together into one comprehensive formula using only pharmaceutical grade (certified) natural extracts. Each of the ingredients has a specific function for enhancing the detox process.
Remember, when preparing for a drug screen, time is your most valuable commodity; the more time you have the more likely you are to be able to detox naturally. Other important variables include frequency of use, quantity of use, metabolic rate and overall health. Home drug test can be used to find out if you’ll definitely fail a lab test but not to find out if you’ll pass; meaning, if you fail a home drug test then it’s essentially guaranteed that you’ll fail a lab test but passing a home drug test doesn’t mean that you’ll pass a lab test. Lastly, if you're short on time, then extra measures like detox kits are an option and should be considered to ensure you pass your test without any issues.
Good luck to all!