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Science Based 15

By

Winston Peki

Will CBD Show Up on A Drug Test?

Will CBD Show Up on A Drug Test

Short answer: no, CBD as a standalone compound does not show up on a drug test.

However, here’s the kicker:

Many CBD products contain a small concentration of THC…

And THC WILL show up on a drug test if taken in large enough concentrations and for a long enough period of time.

But are the low concentrations of THC sometimes present in CBD products, high enough for it to show up on a drug test?

Well, it depends on how much THC exactly is inside your CBD product and how long you have consumed the product.

Today you’re going to learn everything about CBD products and whether you can fail drug tests with them.

Let’s get started.

Summary of Main Points

  • CBD as a standalone compound doesn’t show up on a drug test. CBD doesn’t convert into THC in humans, ever;
  • Drug tests screen for THC and its metabolites. CBD products can contain small concentrations of THC;
  • CBD can inhibit the metabolization of THC, increasing the amount of THC in your system, and increasing your chances to fail a drug test;
  • Whether you’ll fail a drug test after taking THC-containing CBD products is highly dependent on frequency of use, milligrams of THC ingested per dose, and individual metabolization;
  • If you take THC-containing (max 0.3%) CBD products regularly for long periods of time, there’s a chance you’ll fail a urine-based drug test;
  • If you take THC-containing (max 0.3%) CBD products regularly for long periods of time, there’s only a very small chance that you’ll fail a saliva-based drug test;
  • If you take THC-containing (max 0.3%) CBD products regularly for long periods of time, there’s a chance that you’ll fail a breath-based drug test IF you smoke/vape CBD flower;
  • The most sound advice is to avoid THC-containing CBD products if you’re subjected to regular drug tests.

Table of contents:

What’s a Drug Test and Why Should a CBD User Care?

Why Does CBD as a Stand-Alone Compound Not Show Up on a Drug-Test?

Why CBD Can Increase the Time THC Stays in Your System

Why You Can Fail a Drug Test After Taking CBD Products

Urine Drug Tests

Saliva/Mouth Swab Drug Tests

Breath Tests

Conclusion

What’s a Drug Test and Why Should a CBD User Care?

A drug test screens your system for compounds that indicate whether you have used any drugs in the past few hours or days.

They can come in various forms:

  • Urine tests;
  • Saliva or mouth swab tests;
  • Breath tests;
  • Blood tests.

All drug tests also screen for marijuana.

A marijuana drug test screens for delta-9 THC and/or metabolites of delta-9 THC.

Federally legal CBD products don’t contain large concentrations of THC. However, in some cases, these small concentrations can be large enough for you to fail a drug test.

Therefore, if you’re regularly subjected to drug tests, it’s important that you understand how you can fail a drug test by using full-spectrum CBD products.

But first, let’s understand…

Why Does CBD as a Stand-Alone Compound Not Show Up on a Drug-Test?

That’s because marijuana drug tests screen for delta-9 THC or metabolites of delta-9 THC.

Marijuana drug tests never screen for CBD or metabolites of CBD.

Why would they?

CBD isn’t psychoactive and in no way can impair job performance.

Multiple studies have shown that CBD has no negative effects on cognitive performance, memory, or reaction time (1, 2).

Some people think that CBD can convert to THC inside your body.

This is a myth and there’s no scientific evidence showing that CBD converts to THC inside the human body.

There are studies that have shown CBD can convert to THC in vitro, meaning in a cell culture medium (3).

However multiple animal and human studies have shown that CBD doesn’t convert to THC in living organisms (4, 5).

Why CBD Can Increase the Time THC Stays in Your System

What CBD can do is increase THC in your system by inhibiting metabolization.

How?

Because both CBD and THC are metabolized by the same group of CYP450 enzymes. They both compete for the same enzymes (6). So, if CBD ‘reserves’ the available CYP450 enzymes for its own metabolization, there are fewer CYP450 enzymes left for THC’s metabolization, hence THC will stay in your system longer.

One study found that consumption of cannabis that contains both THC and CBD in high concentrations leads to higher blood concentrations of THC than cannabis that’s high on THC but low on CBD (7), confirming this theory.

Therefore, if you used a lot of marijuana and want to get rid of the THC as fast as possible before a possible drug test, we highly advise avoiding any product that contains cannabinoids, whether that’s CBD, CBG, CBN, or any other cannabinoid.

Important note: These CYP450 enzymes are also exactly the reason why combining CBD products with prescription medication can lead to unexpected side effects.

Why You Can Fail a Drug Test After Taking CBD Products

As explained in the introduction, CBD products can contain small concentrations of THC.

The THC concentration inside CBD products can range anywhere between 0.01% to 0.3%.

Now:

Even if you use a CBD product with a THC concentration of 0.3%, it’s unlikely that you’ll experience a ‘high’ or a buzz. That is unless you consume large enough quantities. If for example, you consume 100mg CBD in the form of a CBD oil with 0.3% THC, there’s a chance you’ll experience some psychoactive effects.

The real question though is:

Is a THC concentration between 0.01% and 0.3% enough to fail a drug test?

To understand this, first, we have to look at what limit drug tests detect THC or its metabolites.

Unfortunately, drug tests can differ widely in what they exactly screen for and at what limits.

Most employment-related drug tests are urine tests, so that’s what we’ll focus on next.

Urine Drug Tests

Most urine-based drug tests have a limit of 50 ng/mL THC metabolites (usually THC-COOH). Some urine drug tests use a limit of 20 ng/mL.

The Substance Abuse and Mental Health Services Administration (SAMHSA) implemented a THC > 50ng/mL cutoff for detecting cannabis intake in workplace urine drug testing programs (7).

Professional sports-related drug tests are even stricter. In doping tests, the target analyte is always a metabolite of THC, THC-COOH, and the cutoff is 15 ng/mL.

Some drug tests screen for delta-9 THC, while others screen for metabolites of delta-9 THC. If a drug-test screens for metabolites of delta-9 THC, you need to be more careful because metabolites stay in your system much longer than THC itself. Keep in mind that most urine drug tests screen for metabolites of THC.

Because the lab won’t tell you exactly what they screen for, a safe bet is to expect a screening of THC metabolites, especially THC-COOH.

Now:

This is also exactly the metabolite that stays the longest in your system.

One study looked at how long THC-COOH can be found in urine samples of 12 participants, after smoking a single cannabis cigarette with 70mg THC (8). But since the participants only took 8 puffs, the inhaled THC was estimated to be around 45mg.

In most participants, THC-COOH could be detected up to 72–96 hours after inhaling 45mg THC. The detected concentrations ranged between 3.9 and 38.2 ng/mL THC-COOH. However, only one participant had THC-COOH in his urine at levels of 15 ng/mL or higher at 24 hours after smoking.

Keep in mind, the study participants were light cannabis smokers at most, defined by smoking once or less per month. Also, all participants tested negatively for THC or its metabolites at the start of the study.

Why does this matter?

THC is detected for much longer in urine with chronic cannabis users.

Now:

Let’s translate these numbers to CBD products, starting with a full-spectrum CBD oil that contains 0.2% THC.

An average recommended dose of full-spectrum CBD oil equals 50mg CBD. An average full-spectrum CBD oil contains 5% CBD. So, if you take 50mg CBD with such a product, you will consume 2mg THC per dose.

On the surface, 2mg THC looks significantly less than the 45mg used in the discussed study.

But keep in mind that if you use CBD oil, you probably use it regularly.

Let’s say you used this CBD oil daily for 30 days, now you have ingested 60mg THC over a period of 30 days.

Add to that the fact that studies have shown THC and its metabolites can be detected in urine for a much longer period of time when it’s consumed regularly/chronically…

For example:

One study found that THC-COOH can be found in the urine of a heavy chronic cannabis smoker, for at least 24 days after cessation (9).

And you’ll quickly understand why consuming full-spectrum CBD oil regularly for long periods of time can lead you to fail a drug test, for at least 24 days after you stopped using it.

THC accumulates in fatty tissue and can stay there for a long time (10).

There are many variables that influence how long THC and its metabolites can be detected in urine, but individual metabolism, dose, and frequency of use seem to be the most influential factors.

And although at least one study has shown that orally ingested THC leads to lower blood concentrations than smoked THC, with the same milligrams (11)…

There’s no guarantee you’ll pass a urine drug test if you regularly take full-spectrum CBD oil with up to 0.3% THC.

Therefore, the best advice I can give if you’re regularly subjected to urine drug tests is to either go for a:

  • Broad-spectrum CBD product, or;
  • CBD isolate product.

Saliva/Mouth Swab Drug Tests

Saliva or mouth swab drug tests are sometimes randomly used in the workplace. Other times they’re used after accidents or during random pullovers by the police.

Generally, cannabinoids and their metabolites are detected for a much shorter period of time with a saliva/mouth swab test compared to a urine test.

But how long exactly?

One study that used a Cozart RapiScan to detect how long THC was detectable in saliva after smoking cannabis, found that THC was detectable in saliva up to 2 hours after smoking (12).

A more recent study with newer technology equipment conducted tests to see how long smoked cannabis and cannabis brownies were detectable in saliva tests (13).

They used different cutoff rates to see how long THC would stay detectable, with two different testing devices (DT5000 and DTS2).

They tested smoked cannabis, vaped cannabis, and orally consumed cannabis in the form of brownies, all dosed at 50.6mg THC.

They found the following maximum detection times for the DT5000 device:

  • 5 ng/L THC > 14 hours;
  • 2 ng/L THC > 32 hours;
  • 1 ng/L THC > 44 hours;
  • 0.2 ng/L THC > 44 hours.

And the following maximum detection times for the DTS2 device:

  • 5 ng/L THC > 14 hours smoked/vaped, 8 hours for the orally consumed brownies;
  • 2 ng/L THC > 26 hours;
  • 1 ng/L THC > 26 hours;
  • 0.2 ng/L THC > 50 hours.

Infrequent cannabis users had a shorter detection time than frequent cannabis users. Not surprisingly, the more often you use cannabis, the longer THC stays detectable in your saliva after your last consumption. But the difference was not that significant, it was a matter of hours, not days. And the numbers listed above, include frequent cannabis users.

As you can see depending on the test, it can differ quite significantly as to how long THC stays detectable in your saliva.

Different organizations that make use of saliva drug screenings use different cutoff limits.

For example:

The European Union’s Driving Under the Influences of Drugs, Alcohol, and Medicines (DRUID) project used a THC > 1ng/L confirmatory cutoff for driving under the influence of drugs testing (14). This is based on a saliva test.

Now:

When we look at how much THC you ingest with a full-spectrum CBD oil, for example, we can say that you’ll ingest 2mg THC per CBD dose of 50mg on average.

Can you expect to fail a saliva drug test with 2mg of orally ingested CBD?

Well, let’s look at the numbers.

Let’s take a cutoff of 1ng/L because that’s the strictest cutoff I’ve found to be used.

50.6mg orally consumed THC is detectable at a 1ng/L cutoff anywhere between 26 and 44 hours.

2mg THC is 25-times less of a dose than 50.6mg. It’s highly unlikely that 2mg THC is detectable at all in your saliva at a 1ng/L cutoff.

But there’s no scientific evidence proving that this is indeed the case. Therefore, caution is also advised when using full-spectrum CBD products before you drive.

To be safe, we recommend not using a full-spectrum CBD product before driving on the same day.

Breath Tests

One study found that THC can be detected in breath up to two hours after smoking or vaping cannabis (15).

The same study also found that breath tests can’t detect metabolite THC-COOH.

If you take a CBD tincture, it’s highly unlikely you’ll ever fail a breath-based drug test.

However:

If you smoked CBD flower, there’s a small chance that you’ll fail a breath-based drug test, depending on how much THC was exactly inside your flower.

There’s no THC-free CBD flower, so if you want to be on the safe side, don’t ever smoke or vape CBD flower when driving. There are THC-free CBD vape juices, and those wouldn’t cause you to fail a breath-based drug test.

Conclusion

Based on the data we can say the following:

If you use full-spectrum CBD products regularly, there’s a chance you’ll fail urine-based drug tests up to 24 days after you stop using the product. The longer you have used the product, the longer the metabolites of THC in your system will be detectable in your urine.

If you use full-spectrum CBD products regularly, there’s only a very small chance you’ll fail a saliva-based drug test, as long as you stay within the regular dosing range of anywhere between 20 and 100mg CBD.

If you vape or smoke full-spectrum CBD products regularly, there’s a chance you’ll fail a breath-based drug test for up to two hours after smoking.

If you’re subjected to regular drug tests, we recommend avoiding full-spectrum CBD products. Instead, go for THC-free broad-spectrum or CBD isolate products.

What’s Next…

Go  to our CBD Hub to learn more about CBD-related topics.

Scientific References:

  1. Spindle, T. R., Cone, E. J., Goffi, E., Weerts, E. M., Mitchell, J. M., Winecker, R. E., . . . Vandrey, R. (2020). Pharmacodynamic effects of vaporized and oral cannabidiol (CBD) and vaporized CBD-dominant cannabis in infrequent cannabis users. Drug and Alcohol Dependence, 211, 107937. https://doi.org/10.1016/j.drugalcdep.2020.107937
  2. Thompson, M. D., Martin, R. C., Grayson, L. P., Ampah, S. B., Cutter, G., Szaflarski, J. P., & Bebin, E. M. (2020). Cognitive function and adaptive skills after a one-year trial of cannabidiol (CBD) in a pediatric sample with treatment-resistant epilepsy. Epilepsy & Behavior, 111, 107299. https://doi.org/10.1016/j.yebeh.2020.107299
  3. Merrick, J., Lane, B., Sebree, T., Yaksh, T., O’Neill, C., & Banks, S. L. (2016). Identification of Psychoactive Degradants of Cannabidiol in Simulated Gastric and Physiological Fluid. Cannabis and Cannabinoid Research, 1(1), 102–112. https://doi.org/10.1089/can.2015.0004
  4. Wray, L., Stott, C., Jones, N., & Wright, S. (2017). Cannabidiol Does Not Convert to Δ9-Tetrahydrocannabinol in an In Vivo Animal Model. Cannabis and Cannabinoid Research, 2(1), 282–287. https://doi.org/10.1089/can.2017.0032
  5. Crippa, J. A. S., Zuardi, A. W., Hallak, J. E. C., Miyazawa, B., Bernardo, S. A., Donaduzzi, C. M., . . . Brum Junior, L. (2020). Oral Cannabidiol Does Not Convert to Δ8-THC or Δ9-THC in Humans: A Pharmacokinetic Study in Healthy Subjects. Cannabis and Cannabinoid Research, 5(1), 89–98. https://doi.org/10.1089/can.2019.0024
  6. Yamaori, S., Koeda, K., Kushihara, M., Hada, Y., Yamamoto, I., & Watanabe, K. (2012). Comparison in the In Vitro Inhibitory Effects of Major Phytocannabinoids and Polycyclic Aromatic Hydrocarbons Contained in Marijuana Smoke on Cytochrome P450 2C9 Activity. Drug Metabolism and Pharmacokinetics, 27(3), 294–300. https://doi.org/10.2133/dmpk.dmpk-11-rg-107
  7. Substance Abuse and Mental Health Services Administration. (2017). Mandatory Guidelines for Federal Workplace Drug Testing Programs. Retrieved from https://www.federalregister.gov/documents/2017/01/23/2017-00979/mandatory-guidelines-for-federal-workplace-drug-testing-programs
  8. Brenneisen, R., Meyer, P., Chtioui, H., Saugy, M., & Kamber, M. (2010). Plasma and urine profiles of Δ9-tetrahydrocannabinol and its metabolites 11-hydroxy-Δ9-tetrahydrocannabinol and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol after cannabis smoking by male volunteers to estimate recent consumption by athletes. Analytical and Bioanalytical Chemistry, 396(7), 2493–2502. https://doi.org/10.1007/s00216-009-3431-3
  9. Lowe, R. H., Abraham, T. T., Darwin, W. D., Herning, R., Cadet, J. L., & Huestis, M. A. (2009). Extended urinary Δ9-tetrahydrocannabinol excretion in chronic cannabis users precludes use as a biomarker of new drug exposure. Drug and Alcohol Dependence, 105(1–2), 24–32. https://doi.org/10.1016/j.drugalcdep.2009.05.027
  10. Wong, A., Montebello, M. E., Norberg, M. M., Rooney, K., Lintzeris, N., Bruno, R., . . . McGregor, I. S. (2013). Exercise increases plasma THC concentrations in regular cannabis users. Drug and Alcohol Dependence, 133(2), 763–767. https://doi.org/10.1016/j.drugalcdep.2013.07.031
  11. Huestis, M. (2007). Human Cannabinoid Pharmacokinetics. Chemistry & Biodiversity, 4(8), 1770–1804. https://doi.org/10.1002/cbdv.200790152
  12. Jehanli, A., Brannan, S., Moore, L., & Spiehler, V. R. (2001). Blind trials of an onsite saliva drug test for marijuana and opiates. Journal of forensic sciences, 46(5), 1214–1220. https://pubmed.ncbi.nlm.nih.gov/11569567/
  13. Swortwood, M. J., Newmeyer, M. N., Abulseoud, O. A., Andersson, M., Barnes, A. J., Scheidweiler, K. B., & Huestis, M. A. (2016). On-site oral fluid Δ9-tetrahydrocannabinol (THC) screening after controlled smoked, vaporized, and oral cannabis administration. Forensic Toxicology, 35(1), 133–145. https://doi.org/10.1007/s11419-016-0348-3
  14. Verstraete, Alain & Knoche, Anja & Jantos, Ricarda & Skopp, Gisela & Gjerde, Hallvard & Vindenes, Vigdis & Morland, Jorg & Langel, Kaarina & Lillsunde, Pirjo. (2011). Per se limits – Methods of defining cut-off values for zero tolerance.
  15. Himes, S. K., Scheidweiler, K. B., Beck, O., Gorelick, D. A., Desrosiers, N. A., & Huestis, M. A. (2013). Cannabinoids in Exhaled Breath following Controlled Administration of Smoked Cannabis. Clinical Chemistry, 59(12), 1780–1789. https://doi.org/10.1373/clinchem.2013.207407

Post last updated on: March 29, 2022

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Winston Peki

Reviewing vaporizers, growing supplies, CBD products and scientific articles about cannabis, cannabinoids, and vaping since 2012. Read more about Winston here. LinkedIn

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© Copyright www.herbonaut.com · All Rights Reserved. The content on this website is for informational purposes only and is not intended as medical advice. Medical advice should always be obtained from a qualified medical professional for any health conditions or symptoms associated with them. Every possible effort has been made in preparing and researching this material. We make no warranties with respect to the accuracy, applicability of its contents or any omissions.

Science Based

This article is based on scientific studies, written by Winston Peki and fact-checked by experts.

Inside this article, you can find references to peer-reviewed scientific studies. The numbers in the parentheses (1, 2, …) are clickable links to these peer-reviewed scientific studies. In some cases, the link will give you direct access to the study, while in other cases if you want to read the full study, you either have to pay the publisher a fee or find a free version of the study elsewhere.

Herbonaut is a review and discussion platform that highly values honesty, integrity, and objectivity. We always strive to highlight the benefits, as well as the risks of a specific product or service.

Any topic can be approached from various angles, at Herbonaut we strive to highlight all these angles and will often examine and compare research with contradicting results.

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Scientific References

Spindle, T. R., Cone, E. J., Goffi, E., Weerts, E. M., Mitchell, J. M., Winecker, R. E., . . . Vandrey, R. (2020). Pharmacodynamic effects of vaporized and oral cannabidiol (CBD) and vaporized CBD-dominant cannabis in infrequent cannabis users. Drug and Alcohol Dependence, 211, 107937. https://doi.org/10.1016/j.drugalcdep.2020.107937

Thompson, M. D., Martin, R. C., Grayson, L. P., Ampah, S. B., Cutter, G., Szaflarski, J. P., & Bebin, E. M. (2020). Cognitive function and adaptive skills after a one-year trial of cannabidiol (CBD) in a pediatric sample with treatment-resistant epilepsy. Epilepsy & Behavior, 111, 107299. https://doi.org/10.1016/j.yebeh.2020.107299

Merrick, J., Lane, B., Sebree, T., Yaksh, T., O’Neill, C., & Banks, S. L. (2016). Identification of Psychoactive Degradants of Cannabidiol in Simulated Gastric and Physiological Fluid. Cannabis and Cannabinoid Research, 1(1), 102–112. https://doi.org/10.1089/can.2015.0004

Wray, L., Stott, C., Jones, N., & Wright, S. (2017). Cannabidiol Does Not Convert to Δ9-Tetrahydrocannabinol in an In Vivo Animal Model. Cannabis and Cannabinoid Research, 2(1), 282–287. https://doi.org/10.1089/can.2017.0032

Crippa, J. A. S., Zuardi, A. W., Hallak, J. E. C., Miyazawa, B., Bernardo, S. A., Donaduzzi, C. M., . . . Brum Junior, L. (2020). Oral Cannabidiol Does Not Convert to Δ8-THC or Δ9-THC in Humans: A Pharmacokinetic Study in Healthy Subjects. Cannabis and Cannabinoid Research, 5(1), 89–98. https://doi.org/10.1089/can.2019.0024

Yamaori, S., Koeda, K., Kushihara, M., Hada, Y., Yamamoto, I., & Watanabe, K. (2012). Comparison in the In Vitro Inhibitory Effects of Major Phytocannabinoids and Polycyclic Aromatic Hydrocarbons Contained in Marijuana Smoke on Cytochrome P450 2C9 Activity. Drug Metabolism and Pharmacokinetics, 27(3), 294–300. https://doi.org/10.2133/dmpk.dmpk-11-rg-107

Substance Abuse and Mental Health Services Administration. (2017). Mandatory Guidelines for Federal Workplace Drug Testing Programs. Retrieved from https://www.federalregister.gov/documents/2017/01/23/2017-00979/mandatory-guidelines-for-federal-workplace-drug-testing-programs

Brenneisen, R., Meyer, P., Chtioui, H., Saugy, M., & Kamber, M. (2010). Plasma and urine profiles of Δ9-tetrahydrocannabinol and its metabolites 11-hydroxy-Δ9-tetrahydrocannabinol and 11-nor-9-carboxy-Δ9-tetrahydrocannabinol after cannabis smoking by male volunteers to estimate recent consumption by athletes. Analytical and Bioanalytical Chemistry, 396(7), 2493–2502. https://doi.org/10.1007/s00216-009-3431-3

Lowe, R. H., Abraham, T. T., Darwin, W. D., Herning, R., Cadet, J. L., & Huestis, M. A. (2009). Extended urinary Δ9-tetrahydrocannabinol excretion in chronic cannabis users precludes use as a biomarker of new drug exposure. Drug and Alcohol Dependence, 105(1–2), 24–32. https://doi.org/10.1016/j.drugalcdep.2009.05.027

Wong, A., Montebello, M. E., Norberg, M. M., Rooney, K., Lintzeris, N., Bruno, R., . . . McGregor, I. S. (2013). Exercise increases plasma THC concentrations in regular cannabis users. Drug and Alcohol Dependence, 133(2), 763–767. https://doi.org/10.1016/j.drugalcdep.2013.07.031

Huestis, M. (2007). Human Cannabinoid Pharmacokinetics. Chemistry & Biodiversity, 4(8), 1770–1804. https://doi.org/10.1002/cbdv.200790152

Jehanli, A., Brannan, S., Moore, L., & Spiehler, V. R. (2001). Blind trials of an onsite saliva drug test for marijuana and opiates. Journal of forensic sciences, 46(5), 1214–1220. https://pubmed.ncbi.nlm.nih.gov/11569567/

Swortwood, M. J., Newmeyer, M. N., Abulseoud, O. A., Andersson, M., Barnes, A. J., Scheidweiler, K. B., & Huestis, M. A. (2016). On-site oral fluid Δ9-tetrahydrocannabinol (THC) screening after controlled smoked, vaporized, and oral cannabis administration. Forensic Toxicology, 35(1), 133–145. https://doi.org/10.1007/s11419-016-0348-3

Verstraete, Alain & Knoche, Anja & Jantos, Ricarda & Skopp, Gisela & Gjerde, Hallvard & Vindenes, Vigdis & Morland, Jorg & Langel, Kaarina & Lillsunde, Pirjo. (2011). Per se limits - Methods of defining cut-off values for zero tolerance.

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