The HGV Medical: Your Complete Guide to the D4 Form
The HGV medical is a mandatory health assessment required before you can apply for a provisional HGV licence. It ensures you are physically fit to safely operate large vehicles. This guide explains everything you need to know about the D4 medical examination.
What Is the D4 Medical?
The D4 is a medical examination form prescribed by the DVLA. It must be completed by a registered medical practitioner (doctor) and submitted to the DVLA as part of your application for a provisional HGV (Group 2) driving licence. The examination assesses whether you meet the medical standards required to drive vehicles over 3.5 tonnes.
What Does the Medical Involve?
The D4 medical examination typically takes 30–45 minutes and covers:
- Vision test: You must be able to read a number plate at 20 metres and meet minimum visual acuity standards (with glasses or contact lenses if needed). Your visual field will also be assessed.
- Blood pressure: Your blood pressure must be within acceptable limits. Consistently high blood pressure may require treatment before you can be approved.
- Heart and cardiovascular health: The doctor will listen to your heart and check for any cardiovascular conditions.
- Diabetes screening: You will be asked about diabetes and may have your blood sugar tested. Drivers with insulin-treated diabetes face additional requirements but are not automatically excluded.
- Neurological assessment: Questions about epilepsy, blackouts, and other neurological conditions.
- Mental health: A general assessment of your mental health and any conditions that might affect your ability to drive safely.
- Hearing: A basic hearing assessment.
- General health: Questions about medications, sleep disorders, and any other conditions that might affect driving.
How Much Does the HGV Medical Cost?
The D4 medical is not available on the NHS — you will need to pay privately. Typical costs in 2026 are:
- GP surgery: £50 – £120 (varies by practice)
- Occupational health clinic: £40 – £80 (often faster appointments)
- Online booking services: £45 – £90
Shop around, as prices vary significantly. Some GP surgeries charge a premium, while specialist clinics that process many D4 forms tend to be more competitive.
Common Reasons for Medical Failure
Most people pass the D4 medical without issues, but some conditions can cause problems:
- Uncontrolled high blood pressure: If your blood pressure is consistently above 180/100, you may need to get it under control before reapplying.
- Uncontrolled diabetes: Insulin-treated diabetes requires additional monitoring but does not automatically disqualify you.
- Epilepsy: You must have been seizure-free for at least 10 years (without medication) to hold a Group 2 licence.
- Severe sleep apnoea: Untreated sleep apnoea is a disqualifying condition, but it can usually be managed with CPAP treatment.
- Poor eyesight: If your vision cannot be corrected to the required standard with glasses or lenses.
How to Prepare for Your D4 Medical
- Get your eyes tested: Visit an optician before your medical to ensure your prescription is up to date.
- Know your medical history: Be prepared to discuss any conditions, medications, and previous hospital visits.
- Bring your glasses or contact lenses: If you wear corrective lenses, bring them to the appointment.
- Avoid caffeine and alcohol: These can temporarily raise blood pressure. Avoid them for 24 hours before your appointment.
- Get a good night’s sleep: Being well-rested helps with accurate blood pressure readings.
How Long Is the D4 Medical Valid?
The D4 medical is valid for 4 months from the date of examination. You must submit it to the DVLA within this period. Once your HGV licence is issued, you will need to renew your medical every 5 years until age 65, then annually after that.
Next Steps After Your Medical
Once you have your completed D4 form, send it to the DVLA along with a D2 application form, a passport photo, and your current driving licence. Processing takes 2–4 weeks. Once you receive your provisional HGV entitlement, you can book your theory test and start practical training.
Need help with the medical process? Call GS Driver Training on 01252 447808 — we guide you through every step.