Does Weed Show Up In Urine Tests?



Does weed show up in a urine drug test? And for how long? Find out the answers before taking a test!

Nina Fenton
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The two questions we encounter a lot at Health Street when it comes to urine drug tests are: does weed show up in urine and how long can it be detected? We've been around the drug testing block for a while now, so you've come to the right place to get answers!

Does Weed Show Up in Urine?

These days you're probably not going to sail through life without having to take a urine drug test for one reason or another, which can be an issue if you have a penchant for smoking weed...Unless you're Snoop Dogg or Willie Nelson, of course! This question commonly comes up for those who may be required to submit a urine specimen for employment drug testing purposes, to comply with court ordered drug tests or as part of a custody agreement. The question is rather simple, but the answer is far from it.

So, does weed show up in urine tests? Well, the honest answer is: possibly! Not too comforting if you've got an upcoming test, huh? The reason for this wishy-washy answer is due to the varying factors that are specific to each individual with each factor having the ability to push your test results towards the positive or negative side of the line. Here are the factors that will determine that fate of your urine test:

  • How long it's been since you smoked
  • How often you smoke
  • How fast your metabolism rate is
  • How much you weigh and what your body fat percentage is
  • The percentage of THC in the weed you smoke

Urine drug tests, like those conducted by Health Street, are able to detect both the marijuana in your system and its metabolites. This means that THC, the active component in weed, and the metabolite, THC-COOH, can be found in your urine within mere hours of smoking. It's important to note that your body does not excrete THC-COOH nearly as quickly as it does THC since the metabolite is produced as your liver's way of breaking it down.

Most urine drug tests have a 50 ng/ml threshold cutoff at which marijuana can be detected. It's common for those with results below the threshold cutoff to test positive. Those with results above the threshold will undergo additional testing at 20 ng/ml or lower to accurately determine if the specimen is negative or positive.

How Long Can Weed Be Detected in Urine?

The National Drug Court Institute (NDCI) has conducted studies in an effort to provide a loose idea of the length at which weed can be detected in urine. The following results are based upon the frequency at which marijuana is smoked and upon the last day of usage, according the the NDCI study:

  • Casual or First Time Smokers: Urine tests performed on marijuana users 1 to 4 days after smoking are found to return a positive result more often then not. It is possible to receive negative test results at the end of the fourth day or later depending on the aforementioned factors.
  • Habitual Smokers: Urine tests that are conducted 7 to 10 days after smoking have been found to come back positive. Most users are reported to pass a urine test at the end of tenth day when the 50 ng/ml threshold is used.
  • Long Term Smokers: There is an even less precise means of determining when and if a smoker will test positive for weed when they have been smoking for an extended period of time. Urine tests performed on long term smokers have been known to return positive for over 60 days from the last use. The amount of time between last use and a positive test can fluctuate just as easily as it does for other smokers.

Remember, that there isn't a sure fire way to determine what your test results will be if you smoke or intend to smoke weed thanks to your body's unique way of processing it. So, the only way to guarantee that you will pass a urine drug test is to abstain for as long as possible, and then get a professional 5 Panel Drug Test to check yourself before you apply for that job. If you come up positive, no worries - you can even check your levels to see how close you are to passing next time, so you can estimate how much longer you need to wait.

And finally, a word of advice: please don't waste your time and money on any of the products promising to help you cheat your way to passing a test, either. The FDA hasn't given these products their seal of approval, their claims haven't been supported by professionals in the drug testing industry, and sometimes those products can actually show up in the lab as an attempt at adulteration, which is an automatic failure.

Nina Fenton
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Nina Fenton
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