Can You Drive an HGV With Diabetes? DVLA Rules Explained

Why the rules are stricter for lorries than cars

DVLA splits licences into two groups. Group 1 covers cars and motorbikes. Group 2 covers lorries and buses, so Category C1, C, C+E, D1 and D all fall under it. Because a large vehicle can do far more damage if the driver loses control, the medical standards for Group 2 are higher. With diabetes, the main concern is hypoglycaemia: a low blood sugar episode that can cause confusion or loss of consciousness at the wheel. Almost every rule below exists to reduce that risk.

Type 2 diabetes managed by diet or low-risk tablets

If your type 2 diabetes is controlled by diet alone, or by tablets that do not carry a risk of hypoglycaemia, such as metformin on its own, you can normally hold an HGV licence with no special diabetes conditions. You still need to declare it honestly on the D4 medical form, and you must tell DVLA if you develop complications that affect driving, such as problems with your eyesight or the nerves in your feet and legs.

Tablets that can cause a hypo

Some tablets, mainly sulphonylureas such as gliclazide, can cause low blood sugar. If you take one of these and want lorry or bus entitlement, you must tell DVLA. You will need to show that you have had no severe hypoglycaemia needing help from someone else in the last 12 months, that you have full awareness of hypos, and that you test your blood glucose regularly, at least twice a day and at times relevant to driving.

Type 1 diabetes and insulin

People with type 1 diabetes, and anyone with type 2 who uses insulin, can apply for HGV entitlement, but the conditions are the strictest. DVLA will want to see that you have had no severe hypo in the last 12 months, that you have full hypo awareness, and that you understand the risks. You will usually be asked to show around three months of blood glucose readings stored on a meter with a memory, and you will be assessed by an independent consultant specialising in diabetes. If granted, the licence is normally issued for a maximum of one year at a time, so you renew annually.

• Test your blood glucose at least twice a day, including on days you do not drive.
• Test no more than two hours before you start driving, and every two hours while you drive.
• Keep fast-acting sugar in the cab at all times.
• Check the current GOV.UK guidance on which glucose monitors are accepted for lorry and bus drivers.

How diabetes fits into the HGV medical

Every new lorry or bus driver completes the D4 medical, and it asks directly about diabetes and how it is treated. Answer it fully. If you use insulin or hypo-risk tablets, DVLA will send further forms, and the extra checks can add several weeks before your provisional entitlement comes through. That delay is the main practical effect on your training, so it pays to start early. The medical is included in our course prices, and our HGV medical guide covers the other conditions the doctor checks.

Planning training around a DVLA decision

If you know DVLA will need to assess your diabetes, tell us when you first get in touch. We arrange the medical first, before any driving days are fixed, so you are not committed to dates that a slower DVLA decision could push back. Once your provisional entitlement is on your licence, the theory, training and test can follow in the usual order.

This guide summarises DVLA rules. Your own doctor or diabetes team can advise on your treatment, and GOV.UK has the latest version of the rules.