Medically reviewed by Carmen Fookes, BPharm. Last updated on Oct 30, 2019.
The following variables affect the amount of time that marijuana (THC) and its metabolites remain detectable in the urine or other biological samples:
Theoretically, CBD should not show up on a drug test. However, because most CBD products are classified as a supplement, it is not regulated for safety and purity. This means that contamination of the CBD with THC (tetrahydrocannabinol) may and does occur, and this may show up on a drug test, depending on the cutoff level of the test and other factors listed below.
Drug tests either test for the parent drug or at least one of its metabolites, or both. Concentrations of drugs in urine are usually higher than in blood and present for longer.
An estimate of the length of time marijuana (THC) is detectable in urine is:
If you are concerned that THC in your CBD oil or other CBD product may show up on a drug test, you may be able to reduce the chance of that occurring, though there is no guarantee. Some of the factors that may increase the likelihood of a failed drug test are:
THC can be detected in a urine test for up to 15 days, depending on how often and how much you use. It leaves the bloodstream in about five hours, but substances your body makes from THC (THC metabolites) can show up for as long as 7 days. CBD tends to stay in the bloodstream from 2 to 5 days, depending on dosage and frequency. If you have been using CBD for a while, it can stay in your body for up to 30 days or more.
The legality of CBD products can be confusing. CBD products made from certain cannabis plant varieties are legal only in states where marijuana is legal, due to the potential THC content. CBD products made from hemp variety plants are legal throughout the United States as long as they contain less than 0.3% of THC and do not make any medical claims. (A hemp plant is defined as Cannabis sativa that contains less than 0.3% THC.)
Factors in CBD Oil Showing on Drug Screen
CBD has taken off as a natural remedy for a variety of ailments. CBD products like CBD oil can be made from either the hemp plant or the cannabis plant, which are closely related varieties of the same cannabis species, Cannabis sativa. CBD products contain a cannabinoid—a chemical—called cannabidiol, which does not make you high. The substance in marijuana that causes a buzz is a different cannabinoid, called THC, or tetrahydrocannabinol.
CBD products can still be problematic, however, when it comes to drug testing. Though drug tests screen for THC, not CBD, many CBD products contain a trace amount of THC which will be detected in your bloodstream during a drug test.
Topical products that claim to contain CBD—like shampoos, cosmetics or creams—should not cause any reaction during a drug test because they do not enter the bloodstream. In the case of CBD oils, gummies, teas or transdermal patches, the situation is more complicated. In a test of 84 CBD products obtained online, 18 contained THC.
CBD will not show up in a drug test because drug tests are not screening for it. CBD products may well contain THC, however, so you can fail a drug test after taking CBD products. If you take CBD oil, you should plan accordingly if your work or activities require you to undergo drug testing.
There are many distinctions between marijuana and hemp that relate to CBD oil. Marijuana contains both THC (the psychoactive component) and CBD, whereas hemp contains CBD and only trace amounts of THC. Hemp contains many cannabinoids—CBD is only one example.
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.” The FDA does not regulate these products, and mislabeling is common.
Reasons for Failing a CBD Drug Test
In fact, one study discovered that almost 70 percent of the CBD products sold online were not labeled properly, “causing potential serious harm to its consumers.” The reason for this widespread mislabeling is that CBD products are not strictly regulated by the FDA.
The conclusion is that it’s still theoretically possible for traces of THC metabolites to be present in the stomach acid in the instance where “less-purified CBD productions” are ingested.
In theory, getting a false positive on a drug test from CBD oil should be relatively impossible from pure CBD oil containing less than .3 percent THC. However, because CBD oil is not very well regulated, there is no guarantee that a product contains pure CBD oil, or that its concentration is at a safe or effective level. It is best to use utmost caution and do your research when purchasing a quality CBD oil product to ensure its purity, especially if you need to undergo drug screenings.