A diabetic foot ulcer is an open sore or wound that develops on the foot of a person living with diabetes. These ulcers are one of the most common reasons people with diabetes are admitted to hospital in Canada. They can take weeks or even months to heal, and they are often painless — which makes them easy to miss until they become serious.
Why Does Diabetes Cause Foot Ulcers?
Diabetes affects two key systems in your body: your blood circulation and your nerves. Over time, high blood sugar levels can damage the small blood vessels and nerves in your feet. This condition is called diabetic neuropathy and peripheral vascular disease.
As a result, your feet may lose the ability to feel pain, heat, or pressure normally. You might step on something sharp or develop a blister and never notice it. Furthermore, reduced blood flow means your body has a harder time healing even minor cuts and sores.
This combination — reduced sensation plus slower healing — is what makes diabetic foot ulcers so dangerous. A small scrape that a healthy person heals in days can become a deep, infected wound in someone living with diabetes.
What Does a Diabetic Foot Ulcer Look Like?
A diabetic foot ulcer often appears as a round, crater-like sore on the bottom of the foot, around the heel, or on the tips of the toes. The skin around it may look red, swollen, or calloused. In some cases, you may notice drainage or an unusual odour before you even see the wound clearly.
The colour of the ulcer tells your healthcare provider a lot about how well it is healing. A healthy ulcer that is responding to treatment will appear red or pink inside. However, an ulcer that looks pale, yellow, grey, or black is a warning sign. Dark or blackened tissue means the area is severely damaged and needs urgent medical attention.
Common Locations for Foot Ulcers
The ball of the foot (under the big toe area)
The bottom of the heel
The tips or tops of the toes
Between the toes, where moisture can build up
These spots tend to bear the most pressure during walking, which is one of the main triggers for ulcer formation. According to Mayo Clinic’s overview of diabetic neuropathy, nerve damage in the feet is extremely common in people who have had diabetes for many years.
How Are Diabetic Foot Ulcers Treated?
Treatment for a diabetic foot ulcer involves several steps. Your doctor or a specialist called a podiatrist will guide your care plan. Do not attempt to treat a deep foot ulcer at home on your own — proper medical care is essential to avoid serious complications like infection or bone damage.
Debridement: Removing Dead Tissue
One of the first steps in treating a foot ulcer is debridement. This is the process of removing dead or damaged tissue from the wound. A trained healthcare professional — such as a podiatrist, wound care nurse, or doctor — must perform this procedure.
Here is what typically happens during debridement:
The skin around the wound is cleaned and disinfected.
The provider examines how deep the ulcer is and checks for any foreign objects.
Dead tissue is carefully cut away, and the wound is thoroughly rinsed.
After debridement, the ulcer may look larger or deeper — this is normal and expected.
In addition to manual cutting, doctors may use other methods to clean the wound. These include whirlpool foot baths, irrigation with a syringe or catheter, special enzyme-based gels that dissolve dead tissue, and moist-to-dry dressings. In more complex cases, hyperbaric oxygen therapy may be recommended. This treatment delivers extra oxygen to the wound, which helps speed up healing.
Wound Dressings and Moisture Balance
Keeping a diabetic foot ulcer properly dressed is a critical part of healing. The right dressing does two things: it protects the wound from bacteria and harmful particles from outside, and it keeps the wound environment moist enough to support new tissue growth.
For wounds that are actively draining fluid (called exudate), a powder or absorbent dressing is often applied to draw out moisture. Once the wound stops producing fluid and begins to close, a gel-based dressing is typically used to keep the healing tissue hydrated. Your wound care team will adjust your dressing type as the ulcer progresses through the stages of healing.
Always follow your healthcare provider’s exact instructions about how to change dressings at home. Healthline’s guide on diabetic foot ulcers offers additional helpful context on wound care approaches used today.
Taking Pressure Off Your Foot
Pressure is one of the main reasons diabetic foot ulcers form — and one of the main reasons they fail to heal. Even a few minutes of standing or walking on an unhealed ulcer can reverse days of progress. Therefore, reducing pressure on the affected area is just as important as any medication or dressing.
Your doctor may recommend special footwear, a walking cast, crutches, or even a wheelchair while the ulcer heals. These tools shift weight away from the wound and give it the rest it needs.
Choosing the Right Footwear
Footwear choices matter enormously when you have diabetes. Here are guidelines to follow every day, not just when you have an active ulcer:
Wear shoes made of canvas or leather — materials that allow your feet to breathe.
Avoid plastic, synthetic, or non-breathable shoe materials.
Choose shoes with laces or velcro that you can adjust easily for a proper fit.
Make sure your shoes are not too tight anywhere on the foot.
Avoid pointed toes, high heels, flip-flops, and open-toed sandals.
Never walk barefoot, either indoors or outdoors, unless your doctor specifically says it is safe.
Some people with diabetes may need custom orthopaedic footwear. Talk to your family doctor or podiatrist about whether a referral for custom shoes is right for you. In many provinces, custom diabetic footwear may be covered through your provincial health plan or a supplemental benefits programme — ask your provider about eligibility.
Daily Foot Care Habits to Prevent Ulcers
Prevention is always better than treatment. Building a daily foot care routine is one of the most powerful things you can do if you live with diabetes. These habits can significantly reduce your risk of developing a diabetic foot ulcer in the first place.
Check your feet every day. Look for cuts, blisters, redness, swelling, or any changes in skin colour. Use a mirror to see the bottom of your feet if needed.
Keep your blood sugar well controlled. This is the single most important factor. Good glucose control helps your body heal faster and fight infection more effectively.
Wash your feet daily with mild soap and warm (not hot) water. Dry them carefully, especially between the toes.
Moisturise your feet to prevent dry, cracked skin — but avoid applying lotion between the toes.
Trim your toenails carefully, cutting straight across and not too short.
Manage blood pressure and cholesterol. Both conditions affect circulation and wound healing.
Quit smoking. Smoking dramatically reduces blood flow to the feet and makes healing much harder.
According to Health Canada’s diabetes resources, proper self-management and regular healthcare visits are key to preventing serious diabetes-related complications, including foot ulcers.
When to See a Doctor
If you have diabetes, regular foot check-ups with your family doctor or a podiatrist are essential — even when nothing seems wrong. Your doctor can spot early signs of trouble before they become serious problems. Most provincial health plans in Canada cover diabetes-related medical visits, so do not hesitate to book an appointment.
However, some signs mean you should seek care right away. Visit your family doctor, a walk-in clinic, or an emergency department if you notice any of the following:
Redness, warmth, or swelling around a wound
Pus or discharge coming from a sore
A wound with a foul or unusual odour
Fever or chills
Increasing pain around the ulcer (even if your feet are normally numb)
Hardness or firmness spreading around the wound
An ulcer that has turned white, blue, or black
These symptoms can signal a serious infection. Left untreated, foot infections in people with diabetes can spread quickly and may lead to hospitalisation or, in severe cases, amputation. Always speak with a healthcare professional before starting or changing any treatment for a diabetic foot ulcer.
Frequently Asked Questions About Diabetic Foot Ulcers
What does a diabetic foot ulcer look like in the early stages?
In the early stages, a diabetic foot ulcer may look like a small red sore, a blister, or a patch of irritated skin. Because diabetic foot ulcers are often painless, many people do not notice them until they have grown larger. Check your feet daily and contact your family doctor if you see any unusual sores, even minor ones.
How long does it take for a diabetic foot ulcer to heal?
Healing time for a diabetic foot ulcer varies widely depending on the size, depth, and how well blood sugar and circulation are managed. Minor ulcers may heal in a few weeks with proper care, while deeper or infected ulcers can take several months. Keeping glucose levels well controlled is one of the best ways to speed up healing.
Can a diabetic foot ulcer heal on its own without treatment?
A diabetic foot ulcer is very unlikely to heal safely on its own and should always be evaluated by a healthcare professional. Without proper treatment, a diabetic foot ulcer can become deeply infected and spread to the bone, a condition called osteomyelitis. Early treatment significantly improves outcomes and reduces the risk of serious complications.
Is a diabetic foot ulcer covered under provincial health plans in Canada?
In most Canadian provinces, medical treatment for a diabetic foot ulcer — including doctor visits, wound care, and podiatry referrals — is covered under provincial health insurance plans. Some equipment, such as custom footwear or home dressings, may require supplemental coverage or prior approval. Ask your family doctor or pharmacist what is available in your province.
What is the best way to prevent diabetic foot ulcers?
The best way to prevent a diabetic foot ulcer is to control your blood sugar levels consistently and inspect your feet every single day. Wearing properly fitted, breathable footwear and never walking barefoot also greatly reduces your risk. Regular check-ups with your family doctor or a podiatrist are an important part of your diabetes care programme.
When should I go to a walk-in clinic or emergency room for a foot ulcer?
You should visit a walk-in clinic or emergency room immediately if your diabetic foot ulcer shows signs of infection, such as redness spreading from the wound, pus, a bad odour, fever, or skin that is turning black or blue. These are signs that the infection may be spreading and requires urgent care. Do not wait for a scheduled appointment if these symptoms appear.
Key Takeaways
A diabetic foot ulcer is a serious complication of diabetes that requires prompt medical attention.
Nerve damage and poor circulation caused by diabetes make feet vulnerable to wounds that are slow to heal.
Treatment includes debridement, proper wound dressings, and pressure relief — all managed by a healthcare professional.
Daily foot checks, well-controlled blood sugar, and proper footwear are your best tools for prevention.
Contact your family doctor or a walk-in clinic at the first sign of a foot sore — do not wait for it to worsen.
Always consult your doctor or a qualified healthcare provider before starting any treatment for a foot wound related to diabetes.
