How to Pass a Drug Test: How Long Does Cannabis Stay in Your System?

How to Pass a Drug Test: How Long Does Cannabis Stay in Your System?

Published on 4/23/22

Sure - there are now 36 states with legal medical marijuana and 18 with legalized adult-use marijuana. However, it's still standard policy for many employers to require employees to pass a drug test. Even if you live in a state where marijuana has been fully legalized, there's a chance your employer will require you to pass a drug test, marijuana included. Here's what you need to know about how to pass a drug test and the different types you might run into. 

Different Types of Drug Tests

You might be asked to take several different drug tests in various situations. Drug tests are provided as either 5 or 10-panel options. 5-panel tests usually screen for amphetamines, cocaine metabolites, THC, opiates, and phencyclidine (PCP). 10-panel tests typically screen for the controlled substances tested by the 5-panel test plus barbiturates, benzodiazepines, methadone, methaqualone, and propoxyphene. Either way, if you've been using cannabis, your test will screen for it. Here's a rundown of each drug test and how long it detects marijuana in your system.

Urine Tests

This is by far the most common type of drug test and most frequently used by employers. You've likely had to take this test before. You go to a clinic, take all your belongings out of your pockets, place them in a bin, go into a bathroom, urinate into a small cup, don't flush, and give the cup back to the testing center. Urine tests can detect cannabis metabolites (THC) in your system anywhere from 3 to 30 or more days - the amount of time THC will be in your system is dependent primarily on how frequently you use marijuana.

Saliva Tests


Saliva tests are most commonly used in cases of potential DUIs and are deployed for immediate roadside testing after being pulled over. Only about 10% of employers choose this option for employee tests. These tests are far less common than urine tests but have a similar detection window of roughly three to 30 days. 

Hair Tests

The least likely method used by employers is the hair test, which accounts for roughly 7% of all employment-based drug tests. This is fortunate since THC can be detected from a hair sample for up to 90 days, regardless of how frequently you use cannabis.

Blood Tests


Rarely used in a setting that will get you into trouble, blood tests are primarily administered in laboratory settings. The detection window is much lower than other types of tests, with averages of around one to three days. However, heavy users can have lingering amounts of THC in their blood for up to 25 days after smoking.

How Long it Takes Marijuana to Exit Your System

Regardless of what tactics you use, the most significant factor in deciding how quickly THC will exit your system is the amount of cannabis you consume regularly. Other factors include your natural metabolism, how healthy a lifestyle you lead (working out and lots of water will increase metabolism and decrease the amount of time THC is in your body), and what consumption methods you've used, but the most important is how frequently you use cannabis. Here's a quick breakdown:

One-Time to Infrequent Use: THC can stay detectable within your body for up to three days.

Casual Use: THC can stay detectable within your body anywhere from five days to three weeks, depending on use.

Heavy Use: THC can stay detectable within your body for up to 30 days or more. 

Best Ways to Pass a Drug Test

The best way to ensure that you can pass a drug test is to stay abstinent around the time you're expecting to take a drug test. Of course, that's not always an option if an unexpected or random drug test is requested with a quick turnaround. So, outside of refraining from using cannabis, here are a few tips that should help you pass a drug test a little quicker.

Exercise and a Healthy Diet

A healthy lifestyle isn't much of a solution for last-minute drug tests, but it is something to consider if you think you'll find yourself in the situation. Working out and a healthy diet increases your metabolism over time, which means your body will process THC quicker. Even just 30-minutes of daily exercise can make a difference, but it takes time. 

Drink a Lot of Water and Other Fluids


If you've got a drug test incoming and need to flush your body of THC quickly, the best natural course of action you can take is drinking a lot of water and other fluids. Drinking water increases your urine flow, which dilutes the THC concentration in your body - your goal before a drug test is to dilute below the detection thresholds. In the days leading up to your drug test, drink lots of water and diuretics, which increase urination. Several weak diuretics that you can easily add to your daily routine include coffee and cranberry juice. 

Detox Drinks and Kits

Yes, detox drinks can help quicken the process of getting THC out of your system. Unfortunately, like drinking lots of fluids, detox drinks and kits are not a quick-fix solution. If you're looking for how to pass a drug test in 2 days and you're a heavy user, neither detox kits nor likely anything else will help in that situation. But, if you're wondering how to pass a drug test in a week, that might be enough time if you're a heavy user to apply a detox kit and drink lots of fluids to pass.

At-Home Testing Kits


While this won't help you pass a drug test any quicker, at-home kits may help put your mind at ease. While over-the-counter drug tests aren't as accurate as their professional lab counterparts, they have become increasingly accurate over the last several years. If you can pass a drug test kit at home, you'll likely pass a drug test within 24 hours of taking it. 

Do you know how to pass a drug test fast enough for a day or two turnaround? Let us know if you have any tips we didn't talk about above that helped you pass a drug test in a week or less. Comment below!

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