The D4 medical examination is a fundamental requirement for anyone who wants to drive a large goods vehicle (LGV/HGV) or passenger-carrying vehicle (PCV) professionally in the UK. Unlike the standard driving licence medical, which is self-declared, the D4 requires a face-to-face examination by a registered medical practitioner who completes an official DVLA form. This guide explains everything you need to know about the D4 medical: who needs it, what it involves, the medical standards you must meet, and what happens if you have a condition that might affect your eligibility.
Who Needs a D4 Medical?
You need a D4 medical examination in the following circumstances:
| Situation | D4 Required? | Notes |
|---|---|---|
| First application for HGV/LGV licence (Category C, C+E, C1, C1+E) | Yes | Required before applying for provisional entitlement |
| First application for PCV licence (Category D, D+E, D1, D1+E) | Yes | Required before applying for provisional entitlement |
| Licence renewal at age 45 | Yes | Required for all Group 2 licence holders |
| Licence renewal every 5 years after age 45 | Yes | Required at each renewal |
| Annual renewal after age 65 | Yes | Group 2 licences are renewed annually from age 65 |
| Return after medical suspension | Yes | DVLA may require updated D4 before reinstatement |
It is important to note that the D4 is not the same as a routine GP appointment. You can have the examination carried out by any registered medical practitioner — it does not have to be your own GP. Many drivers choose to use a private occupational health clinic or a doctor who specialises in DVLA medicals, as these practitioners are familiar with the specific standards required and can complete the form efficiently.
What Does the D4 Medical Examination Involve?
The D4 examination is a structured assessment that covers several key areas of health. The examining doctor will complete the official DVLA D4 form, which is then submitted to the DVLA along with your licence application. The examination typically takes 30 to 60 minutes and covers the following:
Eyesight: This is one of the most critical parts of the Group 2 medical. You must be able to read a number plate at 20 metres in good daylight (with glasses or contact lenses if worn). More specifically, you must meet the following visual acuity standards: at least 6/7.5 (0.8) in the better eye, at least 6/60 (0.1) in the worse eye, and a binocular visual acuity of at least 6/7.5 (0.8). You must also have an adequate field of vision — at least 160 degrees horizontal, with no significant defect in the central 30 degrees.
Blood pressure: Your blood pressure will be measured. The DVLA's current guidance is that a blood pressure consistently above 180/100 mmHg may lead to licence refusal or revocation. Drivers with controlled hypertension can usually continue to hold a Group 2 licence provided their blood pressure is adequately controlled.
Cardiovascular health: The doctor will ask about any history of heart disease, angina, heart attack, or arrhythmia. Some cardiac conditions require a period off driving before a Group 2 licence can be held; others may result in permanent revocation.
Neurological conditions: The doctor will ask about any history of epilepsy, stroke, TIA (transient ischaemic attack), or other neurological conditions. Epilepsy is particularly significant — the DVLA's standards for Group 2 licences are considerably stricter than for Group 1 licences.
Diabetes: Diabetes managed by diet alone or by tablets does not usually prevent you from holding a Group 2 licence. However, insulin-treated diabetes requires individual assessment and the DVLA may impose conditions on the licence.
Sleep disorders: Obstructive sleep apnoea (OSA) is increasingly recognised as a significant risk factor for HGV drivers. If you have been diagnosed with OSA, you must inform the DVLA. Drivers with treated OSA can usually continue to hold a Group 2 licence provided they are compliant with their treatment and their symptoms are well controlled.
Mental health: The doctor will ask about any history of significant mental health conditions, including depression, anxiety disorders, or psychosis. Many mental health conditions do not prevent you from holding a Group 2 licence, but the DVLA will assess each case individually.
The Group 2 Medical Standards: Key Differences from Group 1
Group 2 licences (HGV and PCV) are subject to significantly stricter medical standards than Group 1 licences (cars and motorcycles). This reflects the greater risk to public safety posed by large vehicles. The key differences are summarised below:
| Medical Area | Group 1 Standard | Group 2 Standard |
|---|---|---|
| Visual acuity (better eye) | 6/12 (0.5) | 6/7.5 (0.8) |
| Visual acuity (worse eye) | 6/36 (0.17) | 6/60 (0.1) |
| Epilepsy (seizure-free period) | 1 year off driving | 10 years off driving (without medication) |
| Insulin-treated diabetes | Permitted with conditions | Individual assessment required |
| Obstructive sleep apnoea | Must be treated | Must be treated and compliant with CPAP |
| Blood pressure | No specific DVLA limit | Above 180/100 may lead to refusal |
Cost of the D4 Medical
The D4 medical is not available on the NHS — it must be paid for privately. The cost varies depending on the doctor and location, but typically ranges from £50 to £120. Some occupational health clinics offer competitive rates for HGV drivers, and it is worth shopping around. The cost of the D4 is not refundable if the DVLA subsequently refuses your licence application on medical grounds.
When budgeting for your HGV licence, include the D4 medical as a fixed cost. At GS Driver Training, we can recommend local doctors who are experienced in completing D4 medicals efficiently and at competitive rates. A well-completed D4 form reduces the risk of the DVLA requesting further information, which can delay your licence application.
Submitting the D4 Form to the DVLA
Once the D4 examination is complete, the doctor will give you the completed form. You submit this to the DVLA along with your D2 application form (for a new licence) or your renewal application. The DVLA will review the medical information and may contact your doctor or a specialist for further information if needed. Processing times vary, but typically take 3 to 6 weeks for straightforward applications.
If the DVLA has concerns about a medical condition, they may refer your application to their medical advisers or request a specialist report. This can extend the processing time significantly. If you have a known medical condition that may affect your eligibility, it is worth seeking advice from a specialist in DVLA medical standards before submitting your application.
Duty to Inform the DVLA of Medical Changes
Holding a Group 2 licence comes with an ongoing legal obligation to inform the DVLA if your health changes in a way that might affect your fitness to drive. This includes new diagnoses of conditions such as epilepsy, diabetes requiring insulin, heart disease, sleep apnoea, or significant mental health conditions. Failure to inform the DVLA of a relevant medical condition is a criminal offence and can result in a fine of up to £1,000. More seriously, if you are involved in a collision while driving with an undisclosed medical condition, your insurance may be invalidated.
If you are unsure whether a new medical condition or medication needs to be reported to the DVLA, seek advice from your doctor or contact the DVLA's medical enquiries line. It is always better to report and be cleared than to drive without reporting and face the legal and safety consequences.
D4 Medical: Key Facts Summary
| Aspect | Detail |
|---|---|
| Form name | D4 (Medical examination report for a lorry or bus driving licence) |
| Who completes it | Any registered medical practitioner (not necessarily your GP) |
| Cost | £50–£120 (private, not available on NHS) |
| Renewal frequency | At age 45, then every 5 years; annually from age 65 |
| Submitted with | D2 application form to DVLA |
| Processing time | Typically 3–6 weeks for straightforward applications |
| Failure to disclose | Criminal offence, fine up to £1,000, insurance invalidation |
The D4 medical is not a bureaucratic hurdle — it is a safety measure that protects you, your passengers, and other road users. Understanding the standards you need to meet, preparing for the examination, and maintaining your health to the required standard throughout your career are all part of being a professional HGV driver. If you have any concerns about your medical fitness to drive, seek advice early — the earlier a condition is identified and managed, the better your chances of maintaining your licence.
