There is no limit on how many times you can fail a DOT physical. Federal regulations do not cap the number of attempts, and nothing prevents you from retaking the exam as many times as needed. You can even see a different certified medical examiner if you disagree with the first one’s decision.
No Federal Limit Exists
The FMCSA’s Medical Examiner’s Handbook, the document that governs every DOT physical in the country, does not specify any maximum number of failed attempts. If you fail, you’re free to address the medical issue and try again. The regulations also explicitly allow you to get a second opinion from another certified medical examiner on the National Registry if you believe the first examiner’s decision was wrong.
That said, “no limit” doesn’t mean failures are invisible. Every exam result, pass or fail, gets reported to the FMCSA’s National Registry. Medical examiners are required to upload your results by midnight of the next calendar day after your exam. This means your history of examinations is documented, even if no one formally counts your failures against you.
What Happens When You Fail
A failed DOT physical doesn’t result in a permanent mark on your driving record in the way a traffic violation does. What it means practically is that you cannot receive a valid Medical Examiner’s Certificate, and without that certificate, you cannot legally operate a commercial motor vehicle in non-excepted interstate commerce.
If your current certificate expires and you fail the renewal exam, your state’s DMV will be notified through the Commercial Driver’s License Information System (CDLIS). Your commercial driving privileges get downgraded, though your regular non-commercial license stays valid. Law enforcement officers routinely check CDLIS during stops, so driving commercially without a valid medical certificate can get you pulled out of service on the spot.
Why Drivers Fail
Most DOT physical failures come down to a handful of common issues. Vision must meet a minimum of 20/40 in each eye, with or without correction, and you need at least 70 degrees of peripheral vision in both eyes. For hearing, you must perceive a forced whisper at five feet or pass an audiometric test. Blood pressure above 180/110 results in immediate disqualification, while readings in the 140-159/90-99 range may get you a one-year certificate instead of the standard two-year card. Readings between 160-179/100-109 typically limit you to a one-time, one-year certification until you bring the numbers down.
Uncontrolled diabetes requiring insulin was historically disqualifying, though exemption programs now exist. Epilepsy, certain heart conditions, and untreated sleep apnea are other frequent reasons. A history of substance abuse or a positive drug screen will also result in failure. The key word in most of these cases is “uncontrolled” or “untreated.” Many conditions that cause a failure can be managed well enough to pass on a subsequent attempt.
How to Pass After a Failure
If you failed for a specific screening like vision or hearing, the process is straightforward: see a specialist, get treated or corrected, and schedule a new physical. Bring documentation from the specialist showing your condition now meets federal standards. For vision, that might mean updated glasses or a letter from an ophthalmologist. For hearing, it could be properly fitted hearing aids along with an audiometric test showing you meet the threshold.
Blood pressure failures usually require working with your primary care doctor to get your numbers under control, whether through medication, weight loss, dietary changes, or a combination. Bring several weeks of documented blood pressure readings to your next exam to show a sustained improvement, not just one good day.
For conditions like sleep apnea, you’ll typically need compliance data from your CPAP machine showing consistent use. Most examiners want to see at least 30 days of data with usage averaging four or more hours per night.
Seeing a Different Examiner
Federal rules explicitly permit you to get examined by a different certified medical examiner if you disagree with your result. This isn’t considered “doctor shopping” in any formal regulatory sense, and there’s no penalty for doing it. However, every examiner follows the same federal standards, so simply switching examiners without addressing the underlying medical issue is unlikely to produce a different outcome.
Where a second opinion genuinely helps is in borderline cases, situations where medical judgment plays a role. One examiner might interpret a cardiac history differently than another, or weigh your sleep apnea treatment compliance differently. If you believe the first examiner was overly conservative or made an error, seeking another opinion is a reasonable step. Just make sure the new examiner is listed on the FMCSA’s National Registry, as only registered examiners can issue valid certificates.
How Long You Can Drive After a Failure
If you fail a DOT physical while your current certificate is still valid, you can continue driving until that certificate’s expiration date. The failure of a new exam doesn’t retroactively cancel an existing certificate. But once your certificate expires without a valid replacement, your state will downgrade your CDL. In Kansas, for example, the state explicitly warns that CDLIS is updated immediately and that law enforcement can pull you out of service if your records show you’re not medically certified.
The timeline for getting back on the road depends entirely on the condition that caused your failure. A vision correction might take a single eye appointment. Bringing blood pressure under control could take weeks or months. Treating and documenting sleep apnea compliance typically requires at least 30 days. Plan accordingly, especially if your current certificate is close to expiring.