CBD and Drug Tests: Clearing Up the Confusion

Despite the growing popularity of cannabidiol (CBD), there remains a significant amount of confusion about this compound, particularly regarding whether it shows up on drug tests.

CBD and delta-9 tetrahydrocannabinol (THC) are both active constituents of the cannabis sativa plant. However, while THC is known for its intoxicating effects that produce a "high," CBD does not have these psychoactive properties.

Given that both cannabinoids come from the same plant, it's reasonable to wonder if both THC and CBD could show up on a drug test.

To understand this, we need to look at how drug tests for marijuana work and what research says about CBD use and potential positive results.

How Do Cannabis Drug Tests Work?

Drug tests for cannabis are designed to detect THC, not CBD. Dr. Kelly Johnson-Arbor, a medical toxicologist and co-medical director of the National Capital Poison Center, explains that there are several types of drug tests capable of identifying the presence of cannabis in the body.

One of the most common methods is the immunoassay. "In this test, a sample of urine (or other bodily fluids like blood) is analyzed for chemicals resembling the active metabolite of THC," says Dr. Johnson-Arbor.

"The immunoassay does not test for THC itself and does not provide information about the degree of impairment or the amount of THC exposure."

Immunoassays are popular due to their cost-effectiveness and quick results. However, they can yield false positives and negatives, making them presumptive screening tests.

As a result, many organizations use confirmatory drug testing as a follow-up.

"Mass spectrometry, often used for forensic or workplace drug testing, is considered the 'gold standard' because it accurately detects the presence of a drug in urine or blood," Dr. Johnson-Arbor notes.

Mass spectrometry identifies compounds based on their unique chemical structures but is more expensive and time-consuming than immunoassays. It often requires highly trained staff and yields results after several days or weeks.

THC can be detected for up to three days after a single use and over 30 days after heavy use. "THC is fat-soluble and can be stored in body fat, releasing slowly into the bloodstream over time," explains Dr. Johnson-Arbor.

What Level of THC Leads to a Positive Drug Test Result?

There is no universal regulation for THC levels across all drug tests. Different laboratory test manufacturers may have varying requirement levels for positive THC test results.

Typically, the cutoff level for THC is 50 nanograms per milliliter of urine. "This amount represents the concentration of THC metabolites in urine but doesn't reflect the actual amount of THC used," says Dr. Johnson-Arbor.

Does CBD show up on a Drug Exam?

Consuming CBD products could lead to a positive drug test result if the CBD product contains higher levels of THC than indicated on the label. This discrepancy is more common than many might assume.

"CBD products are mostly unregulated and may contain unwanted contaminants, including THC," says Dr. Johnson-Arbor.

"A 2017 study found that less than one-third of 48 analyzed CBD products had accurate labeling regarding CBD concentration, and 21% contained THC."

Regular use of CBD products may, therefore, inadvertently result in a positive drug test if they contain more THC than labeled.

At the same time, CBD itself doesn't produce a high or show up on drug tests; products with higher-than-expected THC levels can.

Does the Type of CBD Matter?

CBD can be derived from hemp (a strain of cannabis sativa) or cannabis containing THC. Hemp-derived CBD should have no more than 0.3% THC, according to the Federal Drug Administration, but product testing has shown it can sometimes exceed this limit.

"Since cannabis possession, growth, and sale remain illegal at the federal level, a positive drug test for THC can have legal consequences, regardless of whether contaminated CBD products caused it," warns Dr. Johnson-Arbor. Broad-spectrum CBD products are less likely to be contaminated with THC due to extraction methods designed to remove THC.

Ensuring CBD Products Don't Contain THC

Consumers need help determining how much THC is in a CBD product. "The CBD industry is largely unregulated, so there is no definitive way to know whether a CBD product contains THC," says Dr. Johnson-Arbor.

Manufacturers may provide test results for their products, but these often represent only a sample batch and do not reflect the composition of all the company's products.

Consumers and patients should look for a Certificate of Analysis (COA), which details the compounds in a CBD product.

The COA is usually found on the company's website or requested directly. If a company doesn't provide a COA, it may be a red flag indicating that it isn't testing its products or withholding test results.

While CBD itself may not show up on a drug test, the unregulated nature of CBD products means there is a risk of THC contamination.

Consumers should take steps to verify the content of CBD products, though there are no guarantees due to the lack of industry regulation.