Guidance

Diabetes mellitus: assessing fitness to drive

Advice for medical professionals to follow when assessing drivers with diabetes mellitus.

✘- Must not drive ! - May continue to drive subject to medical advice and/or notifying DVLA ✓- May continue to drive and need not notify DVLA

Diabetes mellitus

Information sent to drivers

Insulin-treated drivers are sent a detailed letter from DVLA explaining the licensing requirements and driving responsibilities (see the INF294 leaflet in Appendix D).

All drivers with diabetes must follow the information provided in ‘Information for drivers with diabetes’, which includes a notice of when they must contact DVLA (see Appendix D).

Insulin-treated diabetes

Adequate awareness of hypoglycaemia

The Secretary of State’s Honorary Medical Advisory Panel on Driving and Diabetes has defined adequate awareness of hypoglycaemia as whether ‘the licence holder/applicant [is] capable of bringing their vehicle to a safe controlled stop’.

This is a matter of professional judgement and as a guide the duration of hypoglycaemic symptoms experienced should be compatible with bringing a vehicle to a safe controlled stop.

The reliance on alarms on glucose monitoring devices are not accepted as a substitute for adequate symptomatic or physiological awareness of hypoglycaemia experienced by the driver.

Should a driver become reliant on these alarms to advise them that they are hypoglycaemic they must stop driving and notify DVLA.

Impaired awareness of hypoglycaemia

The Panel has also defined impaired awareness of hypoglycaemia for Group 1 drivers as ‘an inability to detect the onset of hypoglycaemia because of total absence of warning symptoms’.

Group 2 drivers must have full awareness of hypoglycaemia.

Severe hypoglycaemia

The law defines ‘severe’ as an episode of hypoglycaemia requiring the assistance of another person.

Group 1 drivers - episodes of hypoglycaemia occurring during established sleep are no longer considered relevant for licensing purposes, unless there are concerns regarding their hypoglycaemia awareness.

Group 2 drivers - must report all episodes of severe hypoglycaemia requiring the assistance of another person, including sleep episodes.

Interstitial glucose monitoring systems

These devices are more widely known as flash glucose monitoring systems (Flash GM) and real-time continuous glucose monitoring systems (RT-CGM).

Group 1

These systems may be used for monitoring glucose at times relevant to driving Group 1 vehicles. Users of these systems must carry finger prick capillary glucose testing equipment for driving purposes as there are times when a confirmatory finger prick blood glucose level is required.

If using an interstitial fluid continuous glucose monitoring system (Flash GM or RT-CGM), the blood glucose level must be confirmed with a finger prick blood glucose reading in the following circumstances:

  • when the glucose level is 4.0 mmol/L or below
  • when symptoms of hypoglycaemia are being experienced
  • when the glucose monitoring system gives a reading that is not consistent with the symptoms being experienced (for example, symptoms of hypoglycaemia and the system reading does not indicate this) - see the INF294 leaflet in Appendix D for further details

Group 2

There is a legal requirement for Group 2 drivers to monitor their blood glucose for the purpose of Group 2 driving.

Flash GM and RT-CGM interstitial fluid glucose monitoring systems are not permitted for the purposes of Group 2 driving and licensing.

Group 2 drivers who use these devices must continue to monitor finger prick capillary blood glucose levels with the regularity defined below.

Group 1 Car and motorcycle Group 2 Bus and lorry
! - Must meet the criteria to drive and must notify DVLA.

All the following criteria must be met for DVLA to license the person with insulin-treated diabetes for 1, 2 or 3 years:

■ adequate awareness of hypoglycaemia (see above)
■ no more than 1 episode of severe hypoglycaemia while awake in the preceding 12 months and the most recent episode occurred more than 3 months ago (see recurrent severe hypoglycaemia guidance below)
■ practises appropriate glucose monitoring as defined below
■ not regarded as a likely risk to the public while driving
■ meets the visual standards for acuity and visual field (see Chapter 6, visual disorders)
■ under regular review
! - Must meet the criteria to drive and must notify DVLA.

All the following criteria must be met for DVLA to license the person with insulin-treated diabetes for 1 year (with annual review as indicated last below):

■ full awareness of hypoglycaemia
■ no episode of severe hypoglycaemia in the preceding 12 months
■ practises blood glucose monitoring with the regularity defined below
■ must use a blood glucose meter with sufficient memory to store 6 weeks of readings as detailed below
■ demonstrates an understanding of the risks of hypoglycaemia
no disqualifying complications of diabetes that would mean a licence being refused or revoked, such as visual field defect (see Chapter 6, visual disorders)

Group 1 and Group 2 requirements for insulin-treated drivers licensed on review

The Secretary of State’s Honorary Medical Advisory Panel on Driving and Diabetes has defined the glucose self-monitoring requirements for licensing as follows.

Group 1 car and motorcycle

  • glucose testing no more than 2 hours before the start of the first journey
    and
  • every 2 hours after driving has started
  • a maximum of 2 hours should pass between the pre-driving glucose test and the first glucose check performed after driving has started
  • applicants will be asked to sign an undertaking to comply with the directions of the healthcare professionals treating their diabetes and to report any significant change in their condition to DVLA immediately

More frequent self-monitoring may be required with any greater risk of hypoglycaemia (physical activity, altered meal routine).

Group 2 bus and lorry

  • regular blood glucose testing – at least twice daily including on days when not driving
    and
  • no more than 2 hours before the start of the first journey
    and
  • every 2 hours after driving has started
  • a maximum of 2 hours should pass between the pre-driving glucose test and the first glucose check performed after driving has started

More frequent self-monitoring may be required with any greater risk of hypoglycaemia (physical activity, altered meal routine), in which case a bus or lorry driver may be licensed if they:

  • use one or more blood glucose meters with memory functions to ensure 6 weeks of readings whilst on insulin that will be available for assessment

How DVLA checks diabetes management requirements for insulin-treated Group 2 bus and lorry licensing

DVLA takes the following measures to ensure the requirements are met for licensing of insulin-treated Group 2 bus and lorry drivers:

  • applicants must stop driving Group 2 vehicles when they commence insulin until DVLA has made a licensing decision
  • arranges an examination to be undertaken every 12 months by an independent consultant specialist in diabetes
  • at the examination, the consultant will require sight of blood glucose self-monitoring records for the previous 6 weeks stored on the memory of a traditional blood glucose meter (not Continuous Glucose Monitoring System)
  • the license application process cannot start until an applicant’s condition has been stable for at least 1 month, and they can provide 2 months of blood glucose readings taken whilst on insulin
  • applicants will be asked to sign an undertaking to comply with the directions of the healthcare professionals treating their diabetes and to report any significant change in their condition to DVLA immediately

Recurrent severe hypoglycaemia guidance

Advice for Group 1 drivers who have had more than one episode of severe hypoglycaemia while awake in the last 12 months

✘- Must not drive and must notify DVLA.

DVLA will then carry out medical enquiries before a licensing decision is made.

Advice for Group 2 drivers after every episode of severe hypoglycaemia in the last 12 months

✘- Must not drive and must notify DVLA following all episodes of severe hypoglycaemia.

Severe hypoglycaemia whilst driving

All Group 1 and Group 2 drivers who experience an episode of severe hypoglycaemia whilst driving must not drive and must notify DVLA.

Impaired awareness of hypoglycaemia – ‘hypoglycaemia unawareness’

Group 1 Car and motorcycle Group 2 Bus and lorry
✘- Must not drive and must notify DVLA.

Driving may resume after a clinical report by a GP or consultant diabetes specialist confirms that adequate hypoglycaemia awareness has been regained.
✘- Must not drive and must notify DVLA.

The licence will be refused or revoked.

Refer to the requirements for insulin-treated diabetes

Diabetes complications

Visual complications – affecting visual acuity or visual field

Group 1 Car and motorcycle Group 2 Bus and lorry
! - May need to stop driving and notify DVLA.

Refer to Chapter 6, visual disorders .
✘- Must not drive and must notify DVLA.

The licence will be refused or revoked.

Refer to insulin-treated diabetes and Chapter 6, visual disorders .

Renal complications

Group 1 Car and motorcycle Group 2 Bus and lorry
! - May need to stop driving and notify DVLA.

Refer to Chapter 7, renal and respiratory disorders.
! - May need to stop driving and notify DVLA.

Refer to Chapter 7, renal and respiratory disorders.

Limb complications – including peripheral neuropathy

Group 1 Car and motorcycle Group 2 Bus and lorry
Any complication such as peripheral neuropathy that means a driver must meet requirements (such as vehicle adaptations) for disabilities ! - May need to stop driving and notify DVLA. See Appendix F, disabilities and vehicle adaptations.

Limb problems or amputations are of themselves unlikely to prevent driving since they may be assisted by suitable vehicle adaptations. The ability to safely control a vehicle at all times is the essential requirement.
! - May need to stop driving and notify DVLA. See Appendix F, disabilities and vehicle adaptations.

Limb problems or amputations are of themselves unlikely to prevent driving since they may be assisted by suitable vehicle adaptations. The ability to safely control a vehicle at all times is the essential requirement.

Temporary insulin treatment – including gestational diabetes or post-myocardial infarction

Group 1
Car and motorcycle
Group 2
Bus and lorry
Trial participants for oral or inhaled insulin are also examples to be included as receiving temporary insulin treatment ! - May drive and need not notify DVLA, provided:

■ under medical supervision
■ not advised by clinician as at risk of disabling hypoglycaemia

! - May continue to drive but must notify DVLA if:

■ disabling hypoglycaemia occurs
■ treatment continues for more than 3 months – or in gestational diabetes, continues for 3 months after delivery
✘- Must notify DVLA and meet the above standards.

Diabetes treated by medication other than insulin

Severe hypoglycaemia

The law defines ‘severe’ as an episode of hypoglycaemia requiring the assistance of another person.

All Group 1 and Group 2 drivers who experience an episode of severe hypoglycaemia whilst driving must not drive and must notify DVLA.

Managed by tablets carrying hypoglycaemia risk

Group 1 Car and motorcycle Group 2 Bus and lorry
Including sulphonylureas and glinides (for example Repaglinide, Nateglinide) ! - May drive and need not notify DVLA, provided:

■ no more than 1 episode of severe hypoglycaemia while awake in the last 12 months and the most recent episode occurred more than 3 months ago
■ should practise appropriate glucose monitoring at times relevant to driving
■ under regular review

It is appropriate to offer glucose monitoring at times relevant to driving to enable the detection of hypoglycaemia.

If the above requirements and those set out in Appendix D are met, DVLA need not be informed.

DVLA must be notified if clinical information indicates the agency may need to undertake medical enquiries.
! - May drive but must notify DVLA. All the following criteria must be met for DVLA to issue a licence for 1, 2 or 3 years:

■ no episode of severe hypoglycaemia in the last 12 months
■ full awareness of hypoglycaemia
■ regular self-monitoring of blood glucose – at least twice daily and at times relevant to driving, i.e. no more than 2 hours before the start of the first journey and every 2 hours after driving has started
■ demonstrates an understanding of the risks of hypoglycaemia
■ has no disqualifying complications of diabetes that mean a licence will be refused or revoked, such as visual field defect

Managed by other medication. Such medication includes Metformin, DPP-4 inhibitors (gliptins), SGLT2 inhibitors, GLP-1 agonists and non-insulin injectables.

Group 1 Car and motorcycle Group 2 Bus and lorry
  ! - May drive and need not notify DVLA, provided the requirements set out in Appendix D are met and the driver is under regular medical review.

! - May drive but must notify DVLA if clinical information indicates the agency may need to undertake medical enquiries.
! - May drive but must notify DVLA. DVLA may issue a licence if the requirements set out in Appendix D are met and the driver is under regular medical review.

A licence is refused or revoked if relevant disqualifying complications have developed, such as diabetic retinopathy affecting visual acuity or visual fields.

A short-term licence may be issued if diabetes complications have developed but the required medical standards have been met.

Diabetes managed by diet/lifestyle alone

Group 1 Car and motorcycle Group 2 Bus and lorry
✓- May drive and need not notify DVLA.

✘- Must not drive and must notify DVLA if, for example:

■ relevant disqualifying complications develop such as diabetic retinopathy affecting visual acuity or visual fields
■ insulin treatment is required (see the requirements for insulin-treated diabetes).
✓- May drive and need not notify DVLA.

✘- Must not drive and must notify DVLA if, for example:

■ relevant disqualifying complications develop such as diabetic retinopathy affecting visual acuity or visual fields
■ insulin treatment is required (see the requirements for insulin-treated diabetes).

Severe hypoglycaemia due to causes other than diabetes management

Examples include hypoglycaemia post-bariatric surgery or in association with eating disorders, and the restriction applies for both car and motorcycle, and bus and lorry drivers.

Severe hypoglycaemia

The law defines ‘severe’ as an episode of hypoglycaemia requiring the assistance of another person.

✘- If there are episodes of severe hypoglycaemia from any cause other than diabetes treatment driving must stop and the driver must notify DVLA

Group 1 Car and motorcycle Group 2 Bus and lorry
The following criteria must be met for DVLA to licence the person experiencing severe hypoglycaemia due to causes other than diabetes management:

■ adequate awareness of hypoglycaemia
■ practices appropriate glucose monitoring as defined in the text below
■ demonstrates an understanding of the risks of hypoglycaemia
■ not regarded as a likely risk to the public when driving
■ remains under regular clinical review for the management of the underlying medical condition
The following criteria must be met for DVLA to licence the person experiencing severe hypoglycaemia due to causes other than diabetes management:

■ full awareness of hypoglycaemia
■ no episode of severe hypoglycaemia in the preceding 12 months
■ practices appropriate glucose monitoring with the regularity defined in the text below
■ demonstrates an understanding of the risks of hypoglycaemia
■ not regarded as a likely risk to the public when driving
■ remains under regular clinical review for the management of the underlying medical condition

Group 1 car and motorcycle

  • glucose testing no more than 2 hours before the start of the first journey
    and
  • every 2 hours after driving has started
  • a maximum of 2 hours should pass between the pre-driving glucose test and the first glucose check performed after driving has started

More frequent self-monitoring may be required with any greater risk of hypoglycaemia (physical activity, altered meal routine).

Group 2 bus and lorry

  • regular blood glucose testing – at least twice daily including on days when not driving
    and
  • no more than 2 hours before the start of the first journey
    and
  • every 2 hours after driving has started
  • a maximum of 2 hours should pass between the pre-driving glucose test and the first glucose check performed after driving has started

More frequent self-monitoring may be required with any greater risk of hypoglycaemia (physical activity, altered meal routine).

Pancreas transplant

Group 1 Car and motorcycle Group 2 Bus and lorry
! - May drive but must notify DVLA.

Licensing is on the provision that the patient has no disqualifying condition.

If the patient is on insulin, refer to insulin-treated diabetes.
! - May drive but must notify DVLA.

Licensing is on the provision that the patient has no disqualifying condition.

If the patient is on insulin, refer to insulin-treated diabetes.

Islet cell transplantation

Group 1 Car and motorcycle Group 2 Bus and lorry
! - May drive but must notify DVLA.

Licensing is on the provision that the patient has no disqualifying condition.

If the patient is on insulin, refer to insulin-treated diabetes.
! - May drive but must notify DVLA.

Licensing is on the provision that the patient has no disqualifying condition.

If the patient is on insulin, refer to insulin-treated diabetes.

Seizures provoked by hypoglycaemia

Seizures provoked by hypoglycaemia now require a period off driving due to the prospective risk of a further seizure.

Group 1 Car and motorcycle Group 2 Bus and lorry
✘ - Must not drive and must notify DVLA.

See ‘Provoked seizures’ under Epilepsy and seizures.
✘ - Must stop driving and must notify DVLA.

See ‘Provoked seizures’ under Epilepsy and seizures.
Published 11 March 2016
Last updated 15 January 2024 + show all updates
  1. Changes to the section 'managed by tablets carrying hypoglycaemia risk' to reflect more accurately the exact requirements for glucose monitoring for Group 1. Changes to the section on 'pancreas transplant' to update requirements for licensing for Group 2. Changes to the section on 'islet cell transplantation' to update requirements for licensing for Group 1 and Group 2. Changes to the time period for glucose monitoring for Group 2 from 3 months to 6 weeks, in order to mirror changes to the D4 in February 2023.

  2. Clarification of medical standard for diabetes managed by medication other than insulin Clarification of medical standard for severe hypoglycaemia due to causes other than diabetes management

  3. Clarification regarding blood glucose reading requirements for Group 2 licensing when insulin treatment is first notified Clarification of medical standards for hypoglycaemia due to causes other than insulin treatment

  4. Confirmation of the need for physiological hypoglycaemic awareness when using Continuous Glucose Monitoring (CGM) devices. Clarification of the required frequency of examination with the applicant’s usual doctor in the case of Group 2 drivers receiving insulin treatment.

  5. Introduction of guidance for the use of continuous glucose monitoring systems for Group 1 driving. Advice regarding severe hypoglycaemia occurring whilst driving.

  6. Clarification of asleep/awake severe hypoglycaemia and relevant timescales of episodes. Clarification of use of CGMS.

  7. As a consequence of changes in European legislation amendments have been required to the applicable standards for: diabetes mellitus managed by insulin; and diabetes mellitus managed by medication which has a risk of causing hypoglycaemia (low blood sugar).

  8. Content updated

  9. First published.