A driver’s physical condition directly affects their ability to control a vehicle. Swedish law requires drivers to report certain medical conditions, and many common medications impair driving ability.
Reportable Conditions
Conditions that affect driving — epilepsy, severe diabetes, heart conditions causing sudden unconsciousness, serious vision impairment, and significant mental health disorders — must be reported to the Swedish Transport Agency (Transportstyrelsen). Continuing to drive when your licence conditions are not met is an offence.
Medication and Driving
Many over-the-counter and prescription medications warn against driving. Antihistamines (allergy tablets) commonly cause drowsiness. Some painkillers, anxiety medications, sleeping pills, and muscle relaxants reduce reaction time and concentration. Always read the package insert and consult a doctor if uncertain.
Vision Requirements
You must be able to read a number plate at 25 metres and meet minimum visual acuity standards. If you need glasses or contact lenses to meet this standard, you must wear them every time you drive — not doing so is illegal. Vision deteriorates gradually and many drivers are unaware their eyesight has declined.
Exam tip: The theory test may ask what you should do if your doctor prescribes medication that affects driving ability. The correct answer: do not drive while taking it unless your doctor confirms it is safe.