Prohibited Medications: A Guide for DOT Safety-Sensitive Employees

For employees in DOT-regulated safety-sensitive roles, the rules regarding prescription and prohibited medications are specific and strictly enforced. Even if a medication is legal under state law or prescribed by a doctor, it may still be prohibited under DOT regulations—particularly within the FAA, which maintains some of the most restrictive guidelines. This blog outlines prohibited medications, the role of Medical Review Officers (MROs), and how drug testing results are reviewed and verified.

Understanding Prohibited Medications in Safety-Sensitive Roles

Prescription Medication Rules:
While a valid prescription may meet general legal standards, DOT agencies, especially the FAA, prohibit certain medications due to their potential impact on safety. Employees must ensure their prescriptions are not only valid and medically necessary but also compliant with agency guidelines.

Methadone Example:
Methadone, though legal and commonly prescribed, is prohibited in safety-sensitive roles due to its sedative effects and safety risks.

The Role of the MRO

MROs are responsible for reviewing positive drug test results and determining whether they are legitimate under DOT regulations.

Employee Contact:

1. After a positive result, the MRO attempts to reach the employee for a verification interview.
2. Employees have 72 hours from notification by the DER to respond.

No Contact?
If the employee cannot be reached within 72 hours (or remains unreachable for 10 days), the MRO is allowed to verify the test as positive without speaking to the employee.

Verification Window:
Even after verification, employees have up to 60 days to present new, credible evidence that could alter the test result.

Handling Complex Cases:
MROs are trained to identify the chemical structure of drugs. For example:

1. Amphetamine vs. Methamphetamine: A claim of Adderall use cannot explain a methamphetamine-positive result, since methamphetamine has a unique molecular structure that the body cannot produce on its own.

Advanced Testing Capabilities

MROs can request additional testing when clarification is needed.

Isomer Analysis:

1. Determines whether methamphetamine came from an illicit source (D-isomer) or an over-the-counter product like Vicks (L-isomer).

THCV Testing:

1. Helps distinguish between pharmaceutical THC (e.g., Marinol) and cannabis-derived THC.

No DOT Approval Needed:
MROs no longer require DOT permission to order these additional confirmatory tests.

What MROs Are Not Allowed to Do

Despite their key role, MROs must adhere strictly to DOT protocols.

Cannot Accept Non-DOT Tests:
Only DOT-certified test results (e.g., urine tests following protocol) can be used. Blood, hair, or third-party lab results are not valid.

Cannot Overlook Procedural Errors:
All test processes must be properly documented using the Custody and Control Form (CCF). MROs cannot act on undocumented errors.

Cannot Override Employer Intent:
If an employer identifies a test as DOT-related, it must follow DOT protocol—even if the SAP or MRO disagrees.

Cannabis Use Not Permitted:
Even with a medical marijuana card, cannabis use is not accepted under any DOT agency for safety-sensitive roles.

Final Thoughts: Staying Compliant with DOT Medication Rules

DOT’s drug testing rules and MRO verification procedures are designed to ensure both fairness and public safety.

For Employees:

1. Know that some medications, even when prescribed, may be banned for your role.
2. Respond quickly to MRO contact and keep your prescriptions current and compliant.

For Employers:

1. Understand the MRO’s role and ensure your testing process follows DOT regulations precisely.

By staying informed and compliant, employees and employers can maintain safety and meet DOT standards.