Eyes & mouth
Oral aphthae (canker sores)
A canker sore is small, but for the week it lasts it can dominate every meal. Pharmacists at Murray Shore Pharmacy in North York assess oral aphthae under OHIP, confirm the ulcer is what it appears to be, and set up relief where appropriate, with clear referral rules for the sores that need more than pharmacy care.
Common signs
- A round or oval ulcer inside the mouth: inner cheek, inner lip, or under the tongue
- A white or grey centre ringed with red
- Sharp pain with acidic, salty, or spicy food
- A burning or tingling spot a day or two before the ulcer appears
- A history of similar sores that heal within one to two weeks
See a doctor instead if
- An ulcer that has lasted more than three weeks without healing
- Sores unusually large, deep, or numerous
- Fever, rash, or joint pain alongside the mouth sores
- So much pain that eating and drinking have become difficult, especially in children
- New ulcers after starting a new medication
Any of these sound like you? Call 416-789-1800 and we will point you the right way — or reach Health811 (opens in a new tab) by calling 811.
How the assessment works
First the pharmacist confirms it is actually an aphthous ulcer: location inside the mouth, its appearance, and your history of previous episodes all feed that call, since cold sores, trauma from braces or a broken tooth, and rarer conditions can all masquerade as canker sores. For a confirmed straightforward sore, a treatment to manage pain and support healing may be prescribed where appropriate, and the visit includes a hunt through your routine for triggers such as certain toothpastes, foods, or recent stress.
Sources 1, 2Three ways to get started. Do it all from home, or come in.
Start online from your phone, call us, or walk in and ask for the pharmacist. No appointment is needed. When you start online, a pharmacist calls or messages you back to finish the assessment. Prefer email? Write to us.
Frequently asked questions
Plain answers from the pharmacy team. Tap a question to open it.
Why do I keep getting canker sores?
There is rarely a single cause, but common contributors include minor mouth trauma, certain toothpaste ingredients, some foods, stress, and low iron or vitamin B12. The assessment reviews your pattern for the contributors you can actually change, and frequent severe episodes earn a referral for blood work.
Can I pass a canker sore to my family?
No. Aphthous ulcers are not infectious, which is one of the clean dividing lines between them and cold sores. Nobody needs separate cups or cutlery on your account.
My ulcer has been there almost a month. Can the pharmacist treat it?
No, and that is deliberate. Any mouth ulcer persisting past three weeks needs a physician or dentist to examine it, because non-healing ulcers have causes a pharmacy assessment cannot rule out. We will help you arrange that instead.
I wear braces and keep getting sores where they rub. Same condition?
Rubbing from braces causes traumatic ulcers, which look similar but are mechanical. The fix starts with orthodontic wax and possibly an adjustment from your orthodontist. The assessment distinguishes the two, and we can still help with the discomfort while the cause is addressed.
What actually happens during the canker sore assessment?
The pharmacist looks at the sore, asks how long it has been there and how often you get them, checks your medications and health history, and screens for the warning signs listed above. It takes about ten to fifteen minutes, and OHIP covers it with a valid health card.
How is a canker sore different from a cold sore?
Location and contagion. Canker sores sit inside the mouth and cannot be passed to anyone; cold sores sit on or around the lips, start as blisters, and are contagious. Each has its own pharmacist assessment, and we handle both.
What can I do at home while the sore heals?
Avoid spicy, acidic, and sharp-edged foods, use a soft toothbrush, and rinse with warm salt water a few times a day. If your toothpaste contains sodium lauryl sulfate, switching brands is worth a try, since that ingredient bothers some people.
Could a white patch in my mouth be thrush instead of a canker sore?
It could. Thrush tends to appear as creamy white patches, while a canker sore is a single defined ulcer with a red border. If you are not sure, come in; oral thrush has its own assessment and we will steer you to the right one.
Can children be assessed for canker sores?
Yes, with a parent or guardian present and the child's health card. Multiple mouth sores in a feverish young child are a different picture, and that gets referred to a physician rather than treated at the counter.
Do I need an appointment?
No. Walk in to 3537 Bathurst Street whenever we are open; assessments happen in the private consultation room. Calling ahead is optional and simply shortens your wait.
What should I bring?
Your Ontario health card, a list of your medications, and anything you have already tried on the sore. If you get these often, a note of how many episodes you have had this year helps the pharmacist decide whether blood work should be suggested to your doctor.
Sources & further reading
Numbered references, linked from the sections above.
Your pharmacist is one call away.
416-789-1800 Call nowPrefer not to call? Email info@murrayshore.com or visit us at Bathurst & Baycrest.