Cannabis Detection Times

How Long Does It Take To Get Below 50ng/ml?

Background

Much of the world hasn’t fully realized the harmlessness nor embraced the benefits of cannabis. Government fueled propaganda campaigns and other movements of cannabis misinformation have had lasting effects that legislature has been slow to correct. One of the unfortunate results of past and present misinformation has been unprovoked and invasive drug screens. Approximately 57 percent of employers require pre-employment drug tests; this doesn’t include the countless other reasons that one might be subjected to testing.

For now, drug screening is a reality that many of us will have to face at one point or another. We’ve put together a complete overview of drug testing for cannabis and provided some guidelines to follow to help you pass them. 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.

Cannabis Is Quickly Metabolized but THC Metabolites Can Linger

The high from using cannabis will often disappear within a few hours, but the actual mechanism that gets one high and that which the labs test for can linger in the system and be detected for up to weeks depending on the frequency and quantity used. The primary psychoactive ingredient in cannabis – Tetrahydrocannabinol, delta-9-THC or simply THC - enters one’s bloodstream soon 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. As you’ve likely heard, 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 later in this article since they are important factors when attempting to come up with a successful detox program.

Drug Screening Methods

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. 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 administered), passing a urinalysis will be our focus.

Urinalysis Detection Times

Some THC metabolites have an elimination half-life of less than 24 hours. Most credentialed experts agree the remainder won’t be released from the body’s fatty tissues for 15 to 30 days. 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 2022) study on detection times has been by the Mayo Medical Laboratories:

This of course is dependent on how often a person smokes (frequency), how much they smoke (quantity), and their metabolism (general health, diet and exercise).

Urinalysis Accuracy

False positives are rare for cannabis due to how commonly it’s tested (because of how often it’s used). Labs are very sophisticated and kept up to date on how individuals cheat these tests. The laboratory first screens the sample with an immunoassay screen (also called an EMIT and or RIA). False positives are rare because if a positive result is returned, the sample is again screened with a backup method called a GCMS, which is much more costly but also much more accurate.

Can You Cheat Your THC Drug Screen?

There are a lot of suggestions online in forums and on YouTube about how to cheat a drug test; as stated before, 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. Some common advice for cheating includes:

• 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 and should be part of any detox program but this should not be relied on as 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. Out of all the ways to cheat a drug test, we recommend these the least. They 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 Naturally?

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 cannabis – 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. 

THC 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.

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!

Additional Guidance

Article resources

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