Traffic safety laws require you to notify the registrar of your provincial motor vehicle licensing authority about any disease that could interfere with your safe driving. Diabetes is one condition that must be reported.

Licensing authorities can request a medical assessment of any licensed driver’s fitness to drive. If safety is a concern, the driver’s license can be issued with conditions, such as a periodic medical, or restrictions. As well, a licence can be suspended until certain conditions are met, or cancelled.

The Canadian Diabetes Association (CDA) believes that everyone with diabetes has a right to be individually assessed for a license to drive. Check out www.diabetes.ca for more information on diabetes and driving (search ‘driving’).

Maintaining your fitness to drive safely

To keep your driver’s license, you must meet certain requirements. You must manage your diabetes properly, and make sure your blood glucose levels are high enough to operate your vehicle safely. Poor blood glucose control can affect your judgment while driving. If you cannot recognize and treat early warning signs of low blood glucose, you risk your safety and the safety of others.

Poor management of diabetes heightens your chance of developing complications that affect your eyes, blood vessels, heart, kidneys and nerves. Such complications can also interfere with your ability to drive safely.

Your doctor also has responsibilities in regard to your diabetes. You must be taught to prevent situations that can affect your ability to drive safely, and how to recognize a severe low blood glucose reaction. Your doctor will also monitor your condition. In most provinces and territories, your doctor must report to the licencing authority if you become unfit to drive.

Type of diabetes treatment and driving

The way your diabetes is treated can affect the class of driver’s license you are allowed to hold.

Treatment with diet - Those whose diabetes is well controlled by diet alone can hold any class of license. They must not have any other medical problems that could affect their ability to drive safely.

Treatment with oral medications - Those whose diabetes is well controlled with medications taken by mouth can also hold any class of license. Again, they must not have other medical problems that could affect driving ability. They cannot be at risk of having low blood glucose reactions while driving.

Treatment with insulin - Those whose diabetes is well controlled with insulin can hold a class 5 license (G in Ontario). They may be eligible for a commercial class of license if they meet specific conditions. They must not have any other medical problems that affect their ability to drive safely. They also cannot be at risk of having low blood glucose reactions while driving.

Low blood glucose warning

Low blood glucose is a major concern if you have diabetes and drive. Knowing more about low blood glucose can help keep you safe behind the wheel. Low blood glucose measures as less than 4 mmol/L on a blood glucose meter. Signs and symptoms can vary greatly from person to person.

You must be able to recognize symptoms you experience when your blood glucose gets low. These symptoms may include:

trembling	confusion	sweating	hunger
difficulty concentrating	anxiety	vision changes	nausea
tiredness or drowsiness	dizziness	weakness	tingling
heart palpitations (rapid, pounding or fluttering heartbeat)		headache

If you cannot recognize your own warning signs of low blood glucose, your blood glucose could drop so low that you pass out while driving.

Medications and risk for low blood glucose

Certain types of medication give you a higher chance of having low blood glucose. Insulin and oral medications that cause the pancreas to release insulin can affect you this way. Such medications include:

glyburide (Diabeta)
gliclazide (Diamicron, Diamicron MR)
glimepiride (Amaryl)
repaglinide (Gluconorm)
nateglinide (Starlix)

Some heart pills, called beta blockers, may hide the symptoms of low blood glucose. Talk to your doctor and pharmacist to find out if any of your medications put you at risk of having a low blood glucose reaction.

Certain situations also increase your risk of having a low blood glucose reaction. They include:

not eating regularly
skipping meals
eating meals later than usual
eating less at a meal than you usually eat
doing more activity than you normally do
drinking alcohol on an empty stomach
having certain gastrointestinal (digestive system) problems
having liver or kidney function problems
Having a history of severe low blood glucose reactions.

Commercial drivers who use insulin to treat their diabetes must meet the following conditions to be considered for a commercial class of license. They must:

earn a certificate showing they know how to measure blood glucose. (A specialist in care of diabetes or a doctor can issue this authorization.)
have had no episodes of low blood glucose that have caused a loss of consciousness or required others to help treat it in the past six months.
have no significant change in insulin therapy. If a significant change does exist, monitoring shows stable and effective blood glucose control.
be able to identify the symptoms of a low blood glucose reaction.
control their diabetes well, with an A1C less than 12 per cent, and less than 10 per cent of their blood glucose levels below 4 mmol/L.
test blood glucose adequately, along with an up-to-date logbook record that can be verified.
understand how to care for diabetes, as well as the causes, symptoms, and treatment of low blood glucose.
have no other medical problems affecting the ability to drive safely.
have an annual or periodic medical review, including an eye (ophthalmologic) exam.
keep a blood glucose meter and a source of fast-acting sugar within reach in their vehicle. Equipment used to deliver insulin must also be with them at all times.
test their blood glucose within an hour of starting to drive, and about every four hours while driving.

In addition:

Commercial drivers must not start to drive or must stop the vehicle if their blood glucose falls below 6 mmol/L. They should eat, and not drive again until blood glucose measures above 6 mmol/L.
The family doctor must approve the work schedule, and consider it to be compatible with insulin treatment.
Criteria for the initial application and annual recertification of a commercial license must be met. Other criteria can exclude a driver from maintaining the license.

How can I continue to drive safely?

Learn all you can about diabetes. If you have not been to a diabetes education class lately, go for an update. The way diabetes is managed changes as new research findings become available.
Test your blood glucose regularly, at different times of the day. Readings taken immediately before you eat, two hours after you begin eating, and before your bedtime snack can tell you how well your blood glucose is being managed. Know what your glucose level should be at these times.
Know how your diabetes medications work. Balance your food, medications, and activity to keep blood glucose in the target range.
Measure your blood glucose level immediately before driving, and at least every four hours while driving (more often if needed).
Always carry your blood glucose meter. An accurate reading is your best indication of a blood glucose problem. Keep a logbook of your readings.
If you take medication to manage your diabetes, make sure you always have a treatment for low blood glucose and a snack on hand. You may be stuck in traffic or delayed on your way home. Prepare for the unexpected!
If you suspect your blood glucose is low, park in a safe and legal place and test. Do not drive if your blood glucose is less than 4 mmol/L. If your blood glucose measures between 4 and 5 mmol/L, do not drive without eating extra food. Commercial drivers should have a blood glucose level greater than 6 mmol/L.
If your blood glucose is less than 4 mmol/L, treat with 15 grams of fast acting carbohydrates, preferably in the form of glucose or sucrose tablets. Wait 15 minutes, then retest. If it is still below 4 mmol/L, treat again. If it is greater than 4 mmol/L, you can have some carbohydrate and protein. Do not resume driving for 45 to 60 minutes after treating a low blood glucose reaction. Ask your doctor or diabetes education team for more information on managing hypoglycemia. Certain factors give you a higher chance of having a severe low blood glucose reaction while driving. They include having had a severe low blood glucose reaction within the last year, having difficulty recognizing such reactions, or having a marked drop in A1C or an A1C within the normal range. (A1C is a test that measures blood glucose control over the last two to three months.) Your family doctor can help by regularly testing how well your diabetes is being managed, and checking for complications.

To assure your own health, manage your diabetes well and be certain your blood glucose levels are within your target range. By making sure that you have your diabetes well under control before driving, you help to keep everyone on the road safe.

For more information on diabetes and commercial drivers, see:

Canadian Council of Motor Transport Administrators (CCMTA)
Determining Driver Fitness in Canada, September 2013: see Part 2, CCMTA Medical Standards for Drivers, chapter 7 on diabetes and hypoglycemia. Website is CCMTA.ca (search: driver fitness).

Canadian Diabetes Association, Guidelines for Diabetes and Private and Commercial Driving at www.diabetes.ca (search driving).

The United States has a Diabetes Exemption Program that allows for case-by-case assessment of commercial drivers. Drivers who use insulin to treat diabetes are allowed to operate commercial vehicles in interstate commerce if they meet certain conditions. Visit the American Diabetes Association at www.diabetes.org (search commercial drivers).

National Safety Code Medical Standards for Drivers with Diabetes
www.diabetes.ca (Search Diabetes and Driving: A Guide for Drivers)

Is it safe to be behind the wheel? Driving and diabetes

It may seem to you that as long as you can keep your diabetes under control, it is your own business. However, once you get behind the wheel of a vehicle, your condition has the potential to affect others.