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Stay on the Road: Avoid Marijuana and Controlled Substances

Drug and alcohol violations bring serious penalties for holders of Commercial Driver's Licenses (CDLs) and Commercial Learner's Permits (CLPs). A positive test will keep you off the road until you complete substance abuse counseling and receive a negative test. It may even cost you your job altogether.


That's why the U.S. Department of Transportation (DOT) urges all professional drivers to exercise caution when considering the use of cannabidiol (CBD) products. While many are sold over the counter for pain relief, anxiety, and movement disorders, some can lead to a positive drug test. Here's why:

  • DOT lists all forms of marijuana as Schedule I controlled substances. That means drivers can't legally use marijuana for recreational or medical reasons, even in states where marijuana use is legal.
  • CBD products contain tetrahydrocannabinol (THC). It's the primary psychoactive component of marijuana.
  • A THC concentration of more than 0.3% will take you off the road following a drug test.
  • CBD products carry misleading labels. Because CBD products aren't regulated by the U.S. Food & Drug Administration (FDA), a CBD product could contain higher levels of THC than the product label indicates.

CBD is not a legitimate excuse for a positive lab test result. Medical Review Officers will verify any drug test at a concentration of 0.3% THC even if a driver claims he or she only used a CBD product. It is the responsibility of the CDL holder to understand and comply with all FMCSA/DOT regulations. This is the law.

Positive drug tests for marijuana remain a problem for drivers. On January 6, 2020, the Federal Motor Carrier Safety Administration (FMCSA) launched its Drug and Alcohol Clearinghouse. It's a secure online database that gives employers, drivers and government agencies real-time access to information about CDL and CLP driver violations.

From January 6, 2020, to May 1, 2021, the FMCSA recorded 69,565 drivers with at least one drug or alcohol violation. Marijuana is the No. 1 violation, accounting for 56% of all positive tests. Other commonly found illegal substances include cocaine, methamphetamine and amphetamine. In all, positive drug tests accounted for 81% of the total violations reported.

The message is clear. Avoid any type of drugs or alcohol, including marijuana and CBD products, so you can stay on the road and keep yourself and others safe.

Drivers who want to view their clearinghouse record can register for the clearinghouse. Visit: clearinghouse.fmcsa.dot.gov/register