What You Need To Know About CBD and Drug Tests

Despite the fact that cannabidiol (CBD) is derived from cannabis—the same plant that marijuana comes from—CBD should not show up on a drug test. That said, it is possible.

Drug tests check for tetrahydrocannabinol (THC) because that is the cannabis compound that makes people feel high. CBD products are typically THC-free but can contain up to 0.3% of THC by law. In some people, that may be enough to yield a positive drug test result.

This article explains why CBD products may show up on a drug test as THC and what to look for in CBD products to prevent a positive drug test.

How to Avoid a Positive CBD Drug Test
Verywell / Brianna Gilmartin

Will CBD Show Up on a Drug Test?

CBD is not measured in drug tests. Instead, drug tests look for tetrahydrocannabinol (THC), which is the element in marijuana that causes a high. CBD oils can have trace amounts of THC even if they're labeled “THC-free.”

What’s the Difference Between CBD and THC?

THC is a psychoactive compound found in the cannabis plant that is mind-altering, causing a "high" sensation.

CBD is a compound extracted from the cannabis plant that does not impair you or cause a "high." CBD can be derived from hemp or non-hemp plants. One reason it’s becoming more popular is that it's said to lack THC.

Most CBD products are made from hemp, not marijuana.

Does CBD Oil Contain THC?

Not all CBD oil products will contain THC, but products can legally contain up to 0.3% THC. For example, low-quality isolates and many full-spectrum tinctures can contain traces of THC. Full-spectrum CBD oil contains other active plant compounds in addition to CBD.

Types of Cannabis

Cannabis is the umbrella term describing hemp and marijuana plants—two different varieties of the Cannabis genus. Both marijuana and hemp can be described as cannabis, but they are two different plants.

The primary difference between hemp and marijuana is that hemp is nearly void of THC.  In fact, hemp is defined as any part of the cannabis plant that contains no more than 0.3% THC.This is why hemp can be legally sold in various products.

There are many distinctions between marijuana and hemp that relate to CBD oil. Marijuana contains both THC (the "high"-inducing element) and CBD. Hemp contains CBD and only trace amounts of THC.

Hemp also contains many cannabinoids—a group of substances found in the cannabis plant. More than 100 cannabinoids have been identified and CBD is one example.

How Much THC Needs to Be Present to Cause a Positive Drug Test?

The active chemical in marijuana that gets detected in a positive drug test screening is THC. If THC is detected in urine at a concentration of 50 nanograms per milliliter (ng/ml), it is a positive test.

Most people are under the impression that CBD oil is THC-free, which is generally true. But not always.

Depending on the source of the cannabis that is used to produce CBD oil, some products do contain traces of THC. This includes low-quality isolates and many full-spectrum tinctures. Full-spectrum CBD oil contains other active plant compounds in addition to CBD.

There are several techniques for extracting CBD oil from the cannabis plant. The extraction method determines whether the CBD oil is an "isolate" or a “full-spectrum oil.”

A CBD isolate is a pure compound with no other active compounds or cannabinoids. The full-spectrum products may include other active compounds, such as cannabinol and cannabis terpenes (the part of the plant that gives the plant its aroma).

How Long Is TCH Detectable in Urine?

Drug tests usually check for THC, the psychoactive component in marijuana. Depending on the frequency of use, THC can be picked up on a test anywhere from a few days for a single use to over a month for heavy daily pot smokers.

Reasons for Failing a CBD Drug Test

There are several common reasons a person can test positive for THC after taking CBD.

Using Product With THC

The most common reason for a failed CBD drug test is that a person is using a CBD oil product that contains THC. This may be a full-spectrum product. Sometimes, though, it could be a low-quality isolate product that contains a small amount of THC.

Although most manufacturers claim their products do not contain THC, this is not always the case.

Cross-Contamination of THC

Very small amounts of THC present in the material that CBD is extracted from can get into the CBD oil in high enough amounts to result in a positive drug test. This scenario may be more likely to occur when CBD oil is purchased from cannabis dispensaries in places where cannabis is legal.

Mislabeled Products

CBD oil extracted from hemp is not supposed to contain more than 0.3% THC. However, it’s not uncommon for sellers to mislabel their products as THC-free hemp when, in reality, it’s a low-quality oil extracted from marijuana, which contains THC. 

In fact, one study discovered that almost 70% of the CBD products sold online were mislabeled. This caused "potential serious harm to its consumers.” The reason for this widespread mislabeling is that CBD products are not strictly regulated by the Food and Drug Administration (FDA).  

How Long Does a CBD Edible Stay in Your System?

CBD edibles take about 30 to 60 minutes to start to take effect. They last five to six hours, depending on your metabolism and dose. A CBD edible may show up on a drug test as THC metabolites for three days. However, if you frequently take CBD edibles, it can take up to 15 days to have a clean urine test.

Secondhand Exposure to THC

Inadvertent exposure to marijuana (via secondhand smoke) is unlikely to be enough to cause a positive drug test result, but it is possible. Being in a room with heavy pot smokers for several hours may cause the inhalation of enough THC-containing smoke to result in a positive test result. 

A more likely secondhand exposure scenario is a positive marijuana hair test. This results from direct contact with marijuana paraphernalia or from another person having THC on their hands.

For instance, say that someone who had direct contact with marijuana then touched your hair. You could feasibly receive a false positive on a drug screening that tests your hair.

CBD Oil Breakdown in the Digestive System

Some sources report that in rare cases, false positive test results have come from CBD oil that breaks down into very small amounts of THC in the stomach. Other studies, however, have refuted this finding.

The conclusion is that it's still theoretically possible for traces of THC to be present in stomach acid when “less-purified CBD productions” are ingested.

Is it Safe To Take CBD While Breastfeeding?

The FDA strongly advises against taking CBD or THC products while nursing. Cannabis products can be excreted through breast milk and are not safe for the baby. Cannabinoids can stay in your milk for up to six days, so "pumping and dumping" may not be a good option.

How to Avoid a Positive CBD Drug Test

If you take CBD oil, you can take steps to try to prevent failing a drug test:

  • Do thorough research to ensure the CBD product you're using is pure and that the company is legitimate
  • Look for manufacturers that have been accredited by the Better Business Bureau
  • Choose manufacturers that use third-party testing for their products
  • Ensure that the CBD oil is an isolate product extracted from a viable industrial hemp supply; It should not be a low-quality tincture.
  • Ask questions about product processing techniques and the possibility of cross-contamination.
  • Avoid secondhand exposure to marijuana use via pot smoking or hair contact from THC users.


CBD oil is usually marketed as THC-free, but that's not always the case. Full-spectrum CBD oils contain other cannabinoids, which may include THC. Isolate products may be contaminated with THC, as well.

Be proactive and thoroughly research products to avoid failing a drug test if you're taking CBD oil. Most important: Ensure that you're using a pure product made by a reputable company.

12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading

By Sherry Christiansen
Sherry Christiansen is a medical writer with a healthcare background. She has worked in the hospital setting and collaborated on Alzheimer's research.