Drug tests are designed to detect the presence of tetrahydrocannabinol (THC), the compound in cannabis that makes people feel high. While routine drug tests don't detect CBD, using hemp oil or other related products can still lead to a positive result. Previous studies have shown that eating hemp foods can cause screening tests to confirm positive results in urine samples. However, there have yet to be any documented cases of people failing a drug test after using hemp oil or personal care products containing hemp oil, such as soaps, shampoos, conditioners, moisturizers, tanning lotions and sunscreens on the skin.
It is possible for someone to fail a drug test for THC-based marijuana in hemp oil, hemp seed, or hemp seed extract, the ingredient in many CBD oils and supplements. Some CBD oils claim to be isolated, but they may actually be full-spectrum oils and contain more cannabinoids (such as THC) than they claim. Even in the worst case scenario, where a person with very compromised skin uses pure hemp oil as a massage oil and leaves it on for 24 hours, the amount of THC that can be absorbed is negligible compared to the amount needed to test positive for a drug test. CBD (cannabidiol) is metabolized by the cytochrome p450 enzymes CYP3A4 and CYP2C19 and can therefore affect the metabolism of drugs that are also metabolized by these enzymes.
A study published in Scientific Reports found that commercial hemp oil skin products contain tiny concentrations of THC and using these products does not create the right conditions for obtaining positive results in tests for THC in urine. Unfortunately, CBD products are not strictly regulated by the Food and Drug Administration (FDA). This has led to accusations of mislabeling, which have been routinely proven false. However, consuming hemp foods that are not commercially produced, hemp-based oils, or using homemade hemp-based products may have risks of testing positive.
It is important to note that while using hemp oil or related products won't cause you to fail a drug test, it is still possible to fail if you are exposed to heavy marijuana smokers for several hours or if you consume hemp foods that are not commercially produced.