📅 Updated July 2026📌 Source: FMCSA, Michigan Secretary of State⏱ 5 min read
A common point of confusion: the DOT physical's urinalysis is not a drug test. Here's how drug and alcohol testing actually works for Michigan CDL holders.
The urinalysis performed during a DOT physical checks kidney function and glucose levels, not for drugs. Drug and alcohol testing is governed by its own separate federal regulations, distinct from the medical certification exam.
The FMCSA Clearinghouse
The FMCSA Drug and Alcohol Clearinghouse is a national database tracking CDL holders' drug and alcohol program violations. Employers must query it before hiring a CDL driver and annually thereafter. This applies nationwide with no state-by-state variation, including Michigan.
The Return-to-Duty Process
A "prohibited" Clearinghouse status blocks all CDL processing until the federal return-to-duty process is completed. No state, including Michigan through its Secretary of State, can issue, renew, upgrade, or transfer a CDL for a driver reported as prohibited until that federal process is fully satisfied.
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