Identifying and Treating a Canker Sore on Your Tonsil

Canker sores are small sores that can occur anywhere in the mouth, usually on the softer parts—even the tonsils. They can be uncomfortable and painful, but they’re common, with more than half the population experiencing them. They are not contagious and usually will go away on their own.

Treatments are available over the counter, and there are measures you can take at home to help reduce pain and encourage healing. This article will discuss canker sores on the tonsils and how to manage them.

Woman feeling pain from a canker sore on her tonsil

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The cause of canker sores is not known, but it’s thought to be a faulty immune system, along with genetics. A malfunction in the immune system happens in which the white blood cells temporarily see the mucosal cells (the cells lining the mucous membranes) as something to be attacked.

Injury to the tissues of the mouth or stress can be a cause. Sometimes it’s a reaction to something you’ve eaten or an ingredient in the food, or to the toothpaste you use. Canker sores also are associated with systemic conditions like Crohn’s disease (an inflammatory bowel disease) or nutritional deficiencies.

Your healthcare provider can examine your canker sores and discuss your medical history, as well as order any blood tests if they suspect you’re deficient in any nutrients.


Your tonsils are organs that are part of the lymphatic system. They reside in the back of your throat and help protect against infection. A canker sore can develop anywhere in your mouth or the back of your throat, including on a tonsil.

A canker sore typically starts as a red spot or bump. Other symptoms can include pain and stinging or burning when you eat or drink certain things or when you move your mouth.

Tingling or burning may even start shortly before you see a red spot or bump. You may or may not be able to see the spot—it might just feel like a sore throat.


Most of the time, the pain from a canker sore goes away on its own within seven to 10 days, and full healing of the sore is seen in one to three weeks. They’re not contagious, so there’s no danger of spreading them to someone else.

There’s no cure for canker sores, so treatment usually focuses on symptom and pain relief. Over-the-counter drops or mouth rinses are available to numb the area. Rinsing with salt water or mouthwashes that don't contain alcohol may be soothing. You can also take Advil (ibuprofen) or Tylenol (acetaminophen) for the pain.

To prevent discomfort, avoid hot, spicy, or acidic foods or beverages until the canker sore is healed. Be sure to maintain good oral hygiene, cleaning between your teeth daily and brushing twice a day.

If the canker sore is caused by a systemic illness, corticosteroids may be prescribed, either in topical form or taken orally, like a tablet. If you have acid reflux, you may want to discuss appropriate acid-reducing medications with your healthcare provider so it doesn't irritate the canker sores.


While you may not be able to completely prevent a canker sore from occurring, you may be able to reduce the likelihood of one forming.

Keep a canker sore diary. Whenever you get a canker sore, take note of what you’ve been eating and drinking and the toothpaste and mouthwash you were using. You may notice some patterns or triggers for the formation of the sore. Noting your stress and fatigue level can also be helpful.

If your canker sore is due to stress, practicing stress-relief techniques like meditation can be helpful.

When to See a Healthcare Provider

If a canker sore doesn’t heal within two weeks, see your dentist or healthcare provider. If the sore is very big, it’s too uncomfortable to eat or drink, or you also have a fever, call your healthcare provider for an appointment. You may have a condition that needs further workup and treatment.


Canker sores are common occurrences, but they can be very painful, especially on the tonsil. You might first notice a red spot or some pain in the area that may be mistaken for a sore throat.

While they usually go away on their own within a week or so, there are some things you can do to help speed up healing and relieve symptoms. This includes avoiding certain foods or drinks that irritate the sore, and using over-the-counter washes or topical treatments. If canker sores are due to a chronic illness, your healthcare provider may prescribe medication.

A Word From Verywell

Canker sores are common and generally harmless, but if you find yourself never without one, or they seem to be happening more often, talk with your healthcare provider. There may be a problem with your nutrition or your immune system. It's best to get professional input and an exam. This way any potential underlying issues can be ruled out and/or treated.

Frequently Asked Questions

  • Is it normal to get a canker sore on your tonsil?

    Yes, it is normal. They’re one of the most common medical conditions affecting the mucosal membranes of the mouth.

  • Will a canker sore go away on its own?

    Yes, a canker sore usually resolves within seven to 10 days. If it doesn't go away after two weeks, see your dentist or healthcare provider. If it's due to a systemic (body-wide) illness, your provider may be able to prescribe medication like corticosteroids.

  • What should you avoid eating if you have a canker sore on your tonsil?

    Avoid eating hot, acidic, or spicy foods. These can irritate your sore and make the pain worse. Try to eat soft, cold, or slightly warm foods that are easy to swallow.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Academy of Oral Medicine. Canker sores.

  2. MedlinePlus. Canker sores.

  3. Canker sores (mouth sores): overview.