Practice question

Why must CDL drivers be careful with prescription or over-the-counter medicines?

  1. Some medicines can cause drowsiness or otherwise affect safe driving ability
  2. Medicines never affect commercial driving
  3. Only illegal drugs matter
  4. Medicine labels do not apply to CDL drivers

Answer: A — Some medicines can cause drowsiness or otherwise affect safe driving ability

The correct answer is shown above. Try the full quiz for additional practice.

Practice more: Iowa CDL General Knowledge Test Practice Questions - Iowa Commercial Driver License General Knowledge Test Exam →