What Happens After a Positive Drug Test?

The MRO Review Process

A positive drug test result from a laboratory is not the end of the process. Before an employer is notified, the result must be reviewed by a Medical Review Officer (MRO) — a licensed physician with specialized training in drug testing.

The MRO contacts the donor (the person who was tested) to ask if there is a legitimate medical explanation for the positive result. If the donor provides documentation of a valid prescription or other legitimate explanation that the MRO accepts, the MRO can verify the result as negative.

Only after the MRO determines there is no legitimate medical explanation is the result reported as a verified positive to the employer.

For DOT-Regulated Testing

Immediate Removal from Safety-Sensitive Duties

When an employer receives a verified positive DOT drug test result, the employee must be immediately removed from safety-sensitive functions. For CDL drivers, this means they cannot drive a commercial motor vehicle. This is not discretionary — it is a federal requirement.

Clearinghouse Reporting

For FMCSA-regulated employers, the verified positive must be reported to the FMCSA Drug and Alcohol Clearinghouse within 3 business days. This creates a federal record that prevents the driver from working for another motor carrier in a safety-sensitive function without completing the return-to-duty process.

Return-to-Duty Process

A DOT employee who tests positive must complete a formal return-to-duty (RTD) process before resuming safety-sensitive functions:

1. Evaluation by a Substance Abuse Professional (SAP)
2. Completion of prescribed education or treatment program
3. Return-to-duty test (must be negative)
4. Follow-up testing: minimum 6 unannounced tests in the first 12 months, potentially continuing for up to 5 years

No Second Chances on Testing

Unlike many non-DOT situations, DOT regulations do not allow an employer to simply let an employee retest. A verified positive is final unless the donor provides a legitimate explanation to the MRO.

For Non-DOT Testing

Non-DOT positive results are governed by employer policy rather than federal regulation. Common employer responses include:

• Pre-employment: Rescind the conditional offer
• Current employee: Offer EAP referral and/or termination depending on company policy
• Some employers: Allow a retest or a second-chance agreement with specific conditions

The right response depends on your written drug-free workplace policy. Whatever your policy says, it must be applied consistently across all employees.

What Employers Should Not Do

• Act on a laboratory result before MRO review is complete
• Discuss the positive result with anyone who doesn't have a need to know
• Violate ADA or state law by improperly considering a past substance use disorder
• Apply the policy inconsistently based on the employee's position or relationship with management

At Do It Right Screening, we manage the full positive result process — MRO review, Clearinghouse reporting, and SAP referrals. Contact us to ensure your program handles positive results correctly.