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How To Pass a Urine Test (Or At Least Stand a Fighting Chance)

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You've got enough to worry about for that upcoming job interview without stressing over whether or not you'll be judged by what you pee into a cup. And sometimes it's just too late to go all the way straight-and-narrow. Fortunately there are ways of maximizing the chance that your future employment won't be sidetracked by Friday night's doobie. Here's what you need to know to have your best chance at passing a urinalysis test.

How Urinalysis Tests Work

Urinalysis is the most overwhelmingly common drug test conducted in the US. In it, urine samples are screened in laboratory conditions for evidence of prior drug ingestion—specifically, they are screened for the metabolic byproducts produced as the body breaks down the drug's active chemicals.

These tests don't actually look for THC, instead they look for its primary metabolite called THC-COOH, typically with a cutoff value of 50 ng/mL. That means that as long as you have 49 nanograms or less of THC-COOH in each milliliter of your urine, you'll pass the test. Simple as that.

When the lab receives your sample, technicians will first split the sample in half. The first half gets subjected to an immunoassay analyzer (these detect the presence of macromolecules by forming and measuring the amount of antibodies produced). If that comes up positive, the second sample is analyzed under a gas chromatography – mass spectrometry (GC-MS) device to confirm the results as well as identify the specific metabolite, and therefore, drug.

Unfortunately for tokers, THC-COOH is fat soluble and metabolizes very slowly. So unlike alcohol, cocaine, methamphetamines, opiates, and a variety of other drugs which are all processed and excreted by the body within 6 to 72 hours, THC-COOH will stay in the body for 5 to 90 days at a time. The more you toke, the longer it will take for your body to process it all—which brings us to the first method of passing your drug test.

The "Don't Smoke Pot for Three Months" Method

Look, it's easy. If your body is going to get rid of the metabolite on its own within 90 days anyway, all you have to do is not introduce any more into your system for that duration. So, stop smoking pot for three months. Maybe go for a run or two, burn off some of that fat and the THC metabolite in it.

Ooooooor maybe not. Maybe it's already too late, or maybe you don't have the willpower. Lucky for you there are a few other (far less surefire) ways to try and pull it off.

The "OK, Just Stop Toking for 30 Days" Method


90 days is what you really need, but abstaining from smoking for just one month will do wonders for your THC-COOH levels. It won't zero them out, but you're not looking to be completely THC-COOH-free but rather just enough so to slip under the mandated 50 ng/mL concentration level. What's more, you can help spur the process on—inciting your body to metabolize the THC-COOH faster—by flushing your system with large amounts of liquid three to four hours before your test.

Water is your best bet. By drinking a couple of liters of H2O, you increase the amount of water in your urine, naturally diluting the sample. This method does come with some caveats however. Consuming massive amounts of water in a short time can lead to dilutional hyponatremia, a potentially fatal condition wherein over-hydration completely disrupts the balance of electrolytes in your body and your brain's neural connections shut down. This is a very rare condition but not entirely out of the realm of possibility.

Second, and much more likely, the sample may be too diluted to test. This is determined at the lab by measuring the concentration of creatine (a naturally-produced metabolite generated by the muscles) in the sample. And if the sample comes back as unusable, it could raise a red flag with the administrator who could well call you back in to take another—supervised—one. Granted, this could buy you more time, but if you need, say, 30-ish more days, you'll probably be hard-pressed to get a delay of game more than once.

This is also why you don't light up a fatty as soon as you get done submitting your sample; there's always a chance they'll make you do it again. And despite what your stoner buddies say, chugging cranberry juice will do nothing but strain your kidneys—its tannins don't interact with THC stored in your fat.

The "Full-On Faking It" Method

Of course, while you do have to submit a urine sample, nobody actually said it had to be your urine. Simply swap your piss for that of a drug-free friend. Wait, what? The administrator just said it does have to be your own urine? Well you're gonna have to sneak this bag of your buddy's pee in with you then.

Behold, The Original Whizzinator. This plastic prosthesis is a fake penis that spurts adulterated urine. It rocketed into the public consciousness when NFL running back Onterrio Smith was caught in an airport with one back in 2006. It allows you to smuggle urine that is not your own into the pee station without having to fill a condom with pee and strap it to the inside of your thigh. What's more, the Whizz can also be filled with synthetic urine as well.

Synthetic urine, which is often sold in smoke shops (go figure), is often the same liquid mixture used to calibrate the lab equipment that will soon be determining your future employment. It isn't a perfect replica for real pee—it doesn't produce a head when poured as real pee does, nor does it have any smell—but is usually close enough to do the job. One more downside is that this liquid may not include uric acid, a metabolite that many labs now look for to ensure the sample is human in origin.

And if you use real, pilfered urine, there are a number of other pitfalls to the switcheroo method. For one, this isn't American Beauty; you can't just keep your stash in the fridge for a rainy day. Once outside of the body, urine immediately begins to oxidize (causing it to darken) and decompose (producing that rank ammonia stench). It doesn't take a PhD in organic chem to figure out that there's something wrong with your sample if you try to hand in week-old urine. That stuff has got to be fresh, like same day—same hour, if you can—for it to work. That makes the logistics tough.

It also has to be warm, like "body temperature" warm. Again, it doesn't take a super-genius to figure out there's something afoot when you turn in an ice-cold sample what was supposedly in your bladder not more than 3 minutes ago. You're not Mr. Freeze. Plus, if this is a monitored test—hope you aren't pee-shy—or you are patted down before entering the pee station, it's going to be hard to explain why you've got a rubber full of the yellow stuff strapped to your leg.

Skip the Snake Oil

Worse than any of the plausible solutions, however dishonest, are the total fakes. Put your wallet away before you buy and strangely colored fluids or syrups. The menagerie of herbal, organic cleanse drinks sold at your local headshop or GNC center are a dime a dozen and generally ineffective. Yes, they'll claim that their specific secret mix of vitamins, herbs, and electrolytes will use "the power of natural and artificial ingredients to block the toxins in your body's fat cells from getting into your urinary tract and helps you to beat the urine drug test" as the DUZ'z IT brand cleanser does, and save your ass for $50 a bottle. However, there is very little evidence (outside of that provided by companies with skin in the game) that these drinks are even modestly effective. And since they're considered herbal supplements, they're not regulated by the FDA—so who knows what's actually in them.

So, there you have it, three means of passing the pee test, presenting in decreasing order of honesty. Or you could, of course, attempt to find an employer that doesn't care about your off-hour proclivities as long as you can get the job done on the clock. [The Weed Blog - Norml]

top image: Rob Byron