List of Drugs that Will Disqualify You from Operating a Commercial Motor Vehicle

Use of medication by CDL operators brings up understandable concerns as to whether or not certain drugs will disqualify a driver from operating a CMV.

In some instances, the situation is straightforward. Drivers are prohibited from taking certain drugs, which can be legal or illegal. In other instances, it depends on the professional opinion(s) of both the DOT medical examiner and the prescribing doctor.

The DOT Drug Testing Panel

Drivers that operate under a DOT drug and alcohol testing program will be have to submit to a pre-employment drug screening, and will be subject randomized testing thereafter. The following substances are included in that screening:

  • Marijuana
  • Cocaine
  • Amphetamines and methamphetamines such as MDMA and MDA
  • Phencyclidine (PCP)
  • Opiates, including Codeine, Morphine, Heroin, Hydrocodone, Hydromorphone, Oxycodone and Oxymorphone

These drugs will fail a CMV test. Additionally, the DOT considers a blood alcohol level of 0.02 percent or greater to be a failing result.

Obviously, testing positive for any of the substances on this list – or a prescribed medication for which the driver does not have a prescription – will disqualify a driver from being able to operate a CMV. While all the drugs on the opioid panel are legal when used as ordered by a certified physician, they will still disqualify a driver from being able to operate under DOT regulations. This is because they are known to impair focus and reaction time, two critical components of safe vehicle operation.

Even when you have a legitimate prescription, drug tests that reveal substances in a driver’s system will probably be marked “Negative with Safety Concern” by the presiding medical review officer (MRO), who will defer to the employer and prescribing physician concerning the driver’s ability to safely drive a CMV.

What Drugs Are on the List?

DOT makes it clear that any driver taking a controlled substance named in 21 CFR 1308.11 (391.42(b)(12)), or another habit-forming substance, is medically unfit to drive. If you take one of the medications on this list, you’ll need your doctor to provide a letter clearing you to drive before you’re due for your next DOT physical.

Drug Use and the DOT Physical

Drivers are mandated to submit to a DOT physical every two years. During these examinations, a driver must disclose any medications or supplements that they take, including those prescribed by a doctor. Remember that the list of DOT disqualifying drugs prohibits the use of narcotics, amphetamines or habit-forming drugs by a CMV operator unless the driver has been cleared for duty by a prescribing doctor. If the driver has a prescription for a controlled substance, their doctor must provide the medical examiner with a written letter that clears the driver for driving.

Even in this event, the medical examiner is not obligated to follow the recommendation of the prescribing doctor. The examiner can still declare the driver unfit based on their consumption of the medication. 

What Happens if You Fail a CMV Drug Test?

The specific consequences of failing a drug test vary from employer to employer, as some have strict no-tolerance policies while others may be more lenient. However, all drivers who fail drug tests must follow the same procedure to return to work.

First, you will be barred from performing safety-sensitive duties, which include operating CMVs. You will remain unable to return to these functions until you successfully complete the Return-to-Duty program.

Your employer will refer you to a substance abuse professional (SAP) who will evaluate you and recommend a specific education or treatment program you will need to complete.

Once you’ve completed the program, you’ll need to undergo a return-to-duty drug test while under observation. Passing this test means you can return to work – failure means repeating the return-to-duty process. Your test results must be:

  • An alcohol level below 0.02 and/or
  • A negative result for controlled substances

You will be subject to a series of follow-up tests. These tests will be conducted at random, and you’ll need to complete at least six tests within 12 months. Failure to produce a negative result – or to comply with these tests – will mean a repeat of the process.

Drug test failures remain on your record after you’ve completed the return-to-duty process.

What if You Get a False Positive?

If you suspect you received a false positive, there’s no need to panic. Drug test samples are normally split in half just in case a false positive happens.

After you’ve met with your medical review officer (MRO), you’ll be able to request a retest within the next 72 hours. They’ll then test the backup sample to verify your results. Results should come in within the next 24 hours.

What if You Refuse a Drug Test?

The consequences for refusing a drug test are the same as those of a failed result. You’ll be removed from performing safety-sensitive functions and made to complete a return-to-duty program. Further refusal to comply will likely result in dismissal from the company.

Trust American Carrier Services for Compliance Assistance Services

At American Carrier Services, we’re dedicated to helping trucking businesses navigate the often confusing legal landscape of DOT and FMCSA regulations. We equip our team of experts with cutting-edge technology to efficiently monitor your company’s compliance. When you choose to work with us, you’ll get proactive alerts of any compliance issues our team finds. You’ll have peace of mind knowing we’ve got your back.

If you have any questions or need assistance, please give us a call at 877-352-1996.