This article is intended to provide a comprehensive review of testing for marijuana and provided some guidelines to help you pass your drug test. Below you’ll learn about how THC is metabolized, drug screening methods, detection times and the different approaches we recommend depending on the amount of time you have to pass your drug test.

We don’t believe that anyone should be subjected to an unprovoked drug screen and hope that you find this useful for the next time you have to visit a lab.

How quickly is THC metabolized? 

As we all know, the high from using marijuana will disappear within a few hours, but the actual mechanism that gets one high and that which labs like Quest Diagnostics test for can linger in the system and be detected for up to weeks. The primary psychoactive ingredient in marijuana – Tetrahydrocannabinol, delta-9-THC or simply THC – enters one’s bloodstream shortly after using. THC is typically only detectable in the bloodstream for 3 to 24 hours because it is quickly metabolized into THC-COOH molecules commonly called THC metabolites. These THC metabolites are stored in fat and gradually released through the body’s natural excretion systems (approximately 20% is excreted in urine, approximately 65% in feces and the remainder in sweat). We’ll address these three natural excretion systems and how to stimulate them later in this article since they are important factors when a successful detox approach to pass your drug test.

What types of drug test are there?

The most well-known drug testing types include hair, saliva, blood and urine. Oral fluid and blood testing is not very common since THC metabolites are typically only detectable in saliva and blood for up to 72 hours and 24 hours, respectively. That being said, they can be common in “incident-response” screenings and unfortunately are very accurate if administered timely. 5 and 10-panel urinalysis screens are much more popular given their cost and extended detection times. Since they’re so much more common (more than 75% of the pre-employment testing), passing a urinalysis will be our focus.

How long is THC detectable?

Some THC metabolites have an elimination half-life of less than 24 hours. Most experts agree the remainder won’t be released from the body’s fatty tissues for 15 to 30 days. This of course is dependent on factors like:

1)      How often a person smokes (frequency);

2)      How much they smoke (quantity);

3)      And their metabolism (general health, diet and exercise).

There have been reports of detection times longer than 30 days but this has been very rare; the most credible source and recent (last updated January 2024 study on detection times has been by the Mayo Medical Laboratories:

• Single Use 3 Days;

• Moderate Use (4 times per week) 5 Days;

• Heavy Use (daily) 10 Days;

• Chronic Heavy Use 30 Days.

Can You Cheat Your THC Drug Screen? 

There are a lot of suggestions online about how to pass a drug test; labs are well aware of these and thus they rarely work. If a drug screen results in a tainted sample, they’ll simply require that you take another. The only time we’d recommend cheating a drug test was during an “incident-response” screen. Some common methods include:

Dilution – This includes drinking a lot of water and urinating several times before the test. This is helpful for lowering THC levels in your system but would not be a fail-safe. We recommend always drinking a healthy amount of water (at the very least eight 8-ounce glasses a day).

Masking Agents – Some companies sell various substances that mask a drug sample. These typically return false positives and require the lab to legally take a second sample, one which the individual often fails.

Tampering – This requires adding something to the urine to contaminate it and through off the lab results. These are even less likely to work than a masking agent, as it will only return a false positive and require the lab to legally take a second sample.

How to Detox? 

Although how long it takes is different for everyone, eventually your body will remove THC from you system through its natural processes. We do not recommend cheating a drug test because of the unlikelihood of success. The good news is that there are ways to boost your body’s excretion systems (urination, feces and sweating) and speed up THC removal.

4 Weeks until Drug Test

If you have four weeks or more until your test then in most cases you won’t need to do anything out of the ordinary other than quit smoking. If you’re in generally good health then your body should naturally metabolize the THC from your system. That being said, if you feel the need to take extra precautions, we’d recommend following the steps from the section below.

3 Weeks until Drug Test

If you have 3 weeks until your test then in most cases you can still pass naturally as long as you’re following habits that would ensure the THC in your system is metabolized. These include:

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 – This will speed up a person’s metabolic rate, burn THC metabolites and remove waste.

2 Weeks until Drug Test

If you have 2 weeks until your test then you start to get into the territory of needing a detox kit, again this depends on frequency and quantity of use as well as overall health. If you’re in infrequent user then we’d recommend following the steps above; if you’re frequent user then recommend you find a reputable herbal detox kit that is gentle on the body. Although there isn’t much scientific evidence to support these products, the logic behind their blends makes sense in aiding the body in removing THC metabolites.

1 Week until Drug Test

If you only have a short amount of time, detox kits that 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 2 Day 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 have a specific function for enhancing the detox process.

24 Hours until Drug Test

Although we’d never recommend waiting until you have 24 hours until a drug test to prepare for it, there could be a time when you don’t have a choice. If a 24 hour notice is a possibility for you, then you may want to keep some synthetic urine handy. The risks associated with these are that the lab will be able to tell and will require you to take a second test.

Conclusion

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!