What Drugs Will Disqualify Drivers from Operating Commercial Vehicles?

The connection between a DOT drug test and prescription drugs can be a muddy one.
Many CDL drivers take prescriptions on a regular basis to treat ailments or help with diagnosed medical conditions. But due to strict DOT drug testing requirements, many wonder whether a particular drug will cause them to fail a drug test and disqualify them from getting behind the wheel.
Plain and simple, there are drugs (both legal and illegal) that drivers are prohibited from taking according to federal regulations. But in other cases, the answer isn't as clear, and it depends on the opinion of both the prescribing doctor and the DOT medical examiner.
To find out which prescription drugs CDL drivers are allowed to take, we need to take a closer look at which drugs they're tested for.
The DOT Drug Test Panel
Drivers who are required to be enrolled in a DOT drug and alcohol testing program will be tested during the pre-employment process, and then periodically afterward, for the following substances:
- Marijuana
- Cocaine
- Amphetamines (Amphetamine, Methamphetamine, MDMA, MDA)
- Opioids (Codeine, Morphine, Heroin, Hydrocodone, Hydromorphone, Oxycodone, Oxymorphone)
- Phencyclidine (PCP)
It probably goes without saying that a positive truck driver drug test result for any illegal substances included on the DOT drug test panel – or a prescription medication that wasn’t prescribed by a medical doctor – will result in a violation of DOT drug testing regulations and must be reported to the DOT Clearinghouse.
Even though the drugs on the Opioid panel are legal when used under the care of a physician, they are considered disqualifying by the DOT because of their ability to impair reaction time and focus.
Even with a prescription, a driver's drug results will likely be marked “Negative with Safety Concern” by a Medical Review Officer (MRO), who will defer them to their employer (and likely their prescribing physician) regarding their ability to drive safely.
Drug Use & DOT Physical Exams
A driver's drug use will inevitably come up during the DOT physical exam process, which occurs at least every two years for most drivers. At the beginning of the examination, the driver will be required to disclose all the medications and supplements they take, whether or not they’ve been prescribed by a doctor.
One thing to keep in mind during this process is the DOT disqualifying drugs list which prohibits the use of any narcotic, amphetamine, or habit-forming drug by a CMV driver unless the prescribing physician clears the driver for duty and writes a letter to the medical examiner that gives the driver clearance to drive.
It’s important to note that the medical examiner's professional opinion can still declare the driver unfit to drive based on their medication usage, even if the prescribing doctor's letter says the opposite.
What Drugs are Prohibited by the DOT?
According to the DOT, any driver that takes a controlled substance that is included in 21 CFR 1308.11 (391.42(b)(12)), or other habit-forming drug, is medically unqualified to drive.
Some of the most commonly known medications on the list are:
- Codeine
- Fentanyl
- Hydrocodone
- Methadone
- Morphine
If any of your drivers take any medications included on this list, they will need a letter from their doctor that clears them to drive before their next DOT physical exam.
If their doctor cannot provide the letter, they may need to reconsider their pain management or medical condition treatment plan to include non-opioid medications, so they can legally and safely drive on behalf of your company and won't need to worry about their DOT drug test and prescription drugs.
All-in-One DOT Drug Testing & DOT Physical Exam Management
As a DOT-regulated business, your company is required to have a DOT drug and alcohol testing program in place, as well as a means of managing DOT physicals. You don't need to keep up with the latest DOT drug testing updates on your own when a reliable third-party administrator (TPA) like Foley can do it for you.
In addition to helping you maintain a drug-free workplace, Foley also provides pre-employment truck driver drug testing, random drug testing, and DOT Clearinghouse query management to keep you compliant with the FMCSA.
And if you're looking for a better way to schedule DOT physicals, Foley has you covered there too.
Find out how easy it can be to stay DOT compliant with a single software solution – schedule a free demo of the Foley platform today.
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