From the Research
To obtain a DOT medical card, you must be at least 21 years old to drive commercial vehicles across state lines (interstate commerce). However, drivers aged 18-20 can qualify for intrastate (within a single state) commercial driving with a DOT medical card, though specific age requirements may vary by state. The medical card itself requires passing a physical examination that evaluates your health conditions, medications, vision (at least 20/40 vision with or without correction), hearing abilities, and overall physical capability to safely operate a commercial vehicle. The standard DOT medical card is valid for up to 24 months, though certain medical conditions may result in shorter certification periods. Drivers with conditions like diabetes, high blood pressure, heart disease, or sleep apnea may receive cards valid for only 3,6, or 12 months, requiring more frequent monitoring. This age requirement exists because interstate commercial driving demands greater experience and maturity due to the increased risks and responsibilities involved in operating large vehicles across different jurisdictions. None of the provided studies 1, 2, 3, 4 directly address the age requirement for a DOT medical card, but they do emphasize the importance of regular health check-ups and monitoring for certain medical conditions, which is also a crucial aspect of maintaining a valid DOT medical card. For instance, study 2 discusses the importance of early detection and treatment of glaucoma, which can affect vision and potentially impact a driver's ability to safely operate a commercial vehicle. Similarly, study 3 highlights the effectiveness of anti-VEGF therapy in treating macular edema due to retinal vein occlusion, which can also affect vision and driving ability. Overall, while the provided studies do not directly address the age requirement for a DOT medical card, they do underscore the importance of regular health monitoring and maintenance, which is a critical aspect of commercial driving.