Ask a Stoner: What Causes a False-Positive Drug Test for THC?

Dear Stoner: Are false-positive drug tests for THC common? If so, what would set them off?
Mattea

Dear Mattea: False THC positives are rare, but have been connected to a short list of substances, the most common and obvious being hemp products. Modified cannabinoids from hemp like Delta-8 and Delta-10 THC will trip that wire every time, while hemp foods and hemp-derived CBD products can cause users to fail tests on occasion. Keep that in mind when you eat a hemp-seed muffin in the morning. Elaine Benes went through this so that you don’t have to.

According to a 2012 study, common baby soaps can trigger positive THC results when added to urine samples, so be careful when washing your hands. In extremely rare cases – we’re talking under 1 percent – anti-inflammatory drugs such as fenoprofen, ibuprofen and naproxen have caused false positives for THC, as have proton pump inhibitors esomeprazole, omeprazole and pantoprazole, which are medications for acid reflux. Efavirenz, an HIV medication, has also accidentally flagged THC tests.

If you’re actually worried about this and not just looking for excuses after failing, wait until you see how many things can create false positives for LSD.

Send questions to marijuana@westword.com.