Diabetes and Driving

Be a responsible driver

It is your responsibility as a driver to:

  • take any prescribed medication, monitor and manage your condition(s);

  • tell the National Driver Licence Service (NDLS) and your insurance provider of any long-term or permanent injury or illness that may affect your ability to drive safely;

  • comply with requirements of your licence as appropriate, including periodic medical reviews; and

  • get professional advice on your medical fitness to drive if you develop a medical condition during the term of your licence.


What is Diabetes?

Diabetes mellitus is a lifelong condition caused by a lack of insulin in your body. Insulin is a hormone that regulates blood glucose (sugar). If some of the treatments for diabetes (particularly insulin and certain types of the tablets) are not managed properly, this can cause ‘hypoglycaemia’ – low blood sugar levels. An episode of hypoglycaemia is sometimes called ‘a hypo’.

Hypoglycaemia makes you feel unwell and can affect your ability to drive safely. If you suffer a severe hypo, it means you need someone to help you – you could become dizzy or drowsy and you need to get your sugar levels under control. In severe cases, you could lose consciousness. The risk of a hypo is the main danger to safe driving for people with diabetes. The risk increases the longer you are on insulin treatment.

If you get warning symptoms of a hypo whilst driving, you must always stop as soon as it is possible to do so safely. Do not ignore the warning symptoms.

Note: You are committing an offence if you carry on driving after you become aware that you are not fit to do so. ‘Awareness’ can be your own awareness – that is, things you notice yourself without being diagnosed by a doctor. Awareness can also be as a result of a warning not to drive from your doctor.


What are the early warning symptoms of Hypoglycaemia?

The early symptoms include:

  • sweating

  • shakiness or trembling

  • feeling weak or hungry

  • fast pulse or palpitations

  • anxiety

  • tingling lips

If you do not get treatment for these early signs, you may experience more severe symptoms such as:

  • slurred speech

  • difficulty concentrating

  • confusion

  • disorderly or irrational behaviour, which may be mistaken for drunkenness

If left untreated, you could lose consciousness.

Drivers with insulin-treated diabetes are advised to take the following precautions to manage their condition and drive safely.



Always carry your glucose meter and blood glucose strips with you. You must check your blood glucose before driving and every two hours whilst driving. Also, always carry personal identification to show that you have diabetes in case of injury in a road traffic accident.


Blood glucose is measured in ‘millimoles per litre’ and is written as mmol/l. If your blood glucose is 5.0 mmol/l or less, have a snack. If it is less than 4.0 mmol/l or you feel hypoglycaemic, do not drive. Take appropriate action. Retest to ensure your blood glucose is above 5.1 mmol/l.


If you develop hypoglycaemia while driving, stop your vehicle as soon as possible.


Switch off the engine, take the keys out of the ignition, and move from the driver’s seat. Do not drive again until 45 minutes after your blood glucose level has returned to normal. It takes up to 45 minutes for the brain to recover fully.


Keep an emergency supply of fast-acting carbohydrates, such as glucose tablets or sweets, within easy reach in your vehicle.


Always take regular meals, snacks and rest periods at least every two hours on long journeys.


Always avoid alcohol.


Please make sure that your meter displays the correct time and date so that you have a record.


Driver Guidelines

Group 1 – Driving a car, motorcycle or tractor

If you are a Group 1 driver, you must inform NDLS if:

  • you suffer more than one episode of severe hypoglycaemia (where you need someone to help you) within the last 12 months.

Group 2 – Driving a bus or truck

If you are a Group 2 driver, you must inform NDLS if:

  • you suffer one episode of severe hypoglycaemia;

  • your medical team feels you are at high risk of developing hypoglycaemia;

  • you begin to have difficulty in recognising warning symptoms of low blood sugar (impaired awareness of hypoglycaemia);

  • you suffer severe hypoglycaemia while driving;

  • an existing medical condition gets worse, or you develop any other condition that may affect safe driving.

If you are a Group 1 or Group 2 driver applying for, or renewing your licence, or if you have been diagnosed with diabetes, you must inform NDLS if:

  • you are treated by insulin, or if your diabetes is managed by tablets which carry a risk of inducing hypoglycaemia (bringing on a hypo attack), for example sulphonylureas. (Ask your doctor whether you are on sulphonylureas or other medications which carry a risk of inducing hypoglycaemia.)

  • you develop any problems with your circulation or sensation in your legs or feet which makes it necessary for you to drive certain types of vehicles only (for example, automatic vehicles or adapted vehicles).

If you are on temporary insulin treatment, you should consult with your doctor as to whether or not you must notify the NDLS.

There is no need to notify the NDLS if your diabetes is managed by diet alone, or only by medications which do not carry a risk of inducing hypoglycaemia.


Diabetes and eyesight

  • Diabetes may affect your eyesight. You should have an eye test at least every year carried out by a doctor or optometrist or orthoptist. They might recommend that you have more frequent tests at regular intervals. These tests should be a full examination including the back of the eye.


What will happen if I still drive?

It is important to strike a balance between mobility and safety. If you continue to drive against medical advice or ignore early warning symptoms, and evidence is found of this, it will affect your insurance, and the NDLS and Garda will take action to remove your licence.


How do I inform the NDLS?

If, following consultation with your GP, your medical condition is one that needs to be notified to the NDLS, you need to complete forms (1) and (2) below and return in person to any NDLS centre.

You need to bring:

  1. a completed Driver Licence Application Form;

  2. a Medical Report Form (D501) completed by your doctor (a letter from your doctor is not accepted);

  3. proof of your PPSN; and

  4. your current licence.

You will then, within a specified time frame, be issued with a new, updated licence.

Please see www.ndls.ie for locations/bookings and forms.

If you have more questions, please email medicalfitness@rsa.ie or telephone 1890 40 60 40.

Please note if you have supplied a medical report form to obtain your existing licence or permit and the terms of licence or permit are not being altered, you may submit your new application together with your medical report form by post to:

National Driver Licence Service PO Box 858 Southside Delivery Office Co Cork


Further information sources:

  • Your GP or nurse.

  • Diabetes Ireland is a valuable source of support and information.

Web: www.diabetes.ie

Helpline: 1850 909 909

Email: info@diabetes.ie