Overview

• Opioid painkillers, tranquillisers and some antidepressants can impair driving, especially when they cause drowsiness or carry “do not operate heavy machinery” warnings.
• Drivers must notify the DVLA if a condition or medicine affects safe driving, typically by completing the M1 questionnaire and seeking medical advice if unsure.
• After notification, the DVLA may request GP or consultant reports, medical exams, eyesight checks or driving assessments before issuing a decision letter.
• Most motorists can keep driving during a DVLA review, though referrals can extend processing times and specific guidance applies at licence renewal.
• NHS guidance and police enforcement also cover illness and some over-the-counter cold and flu remedies that cause impairment, which can lead to drug-driving or careless driving charges.