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Exploring Canker Sore: Treatment, Causes, Symptoms, and More



Canker sores in mouth are small, painful ulcers that can make eating, drinking, and even speaking difficult. But what causes them? And what can you do to find relief? In this guide, we'll discuss the causes and symptoms of canker sores, shedding light on why they occur and how they manifest. More importantly, we'll explore a range of effective home remedies you can use to ease the pain and accelerate healing. Read on to know more!

What are canker sores?

Canker sores, also known as aphthous ulcers, are small, painful lesions that develop inside your mouth. These shallow sores typically appear on the soft tissues of your inner cheeks, lips, tongue, or the base of your gums. Canker sores are often round or oval-shaped with a whitish or yellowish centre and a red border.

Who gets canker sores?

Canker sores can affect anyone, but people who have allergies are more prone to developing them than others. If you find yourself frequently dealing with these painful ulcers, you're not alone. They're a common oral health issue, with about 20% of the population experiencing them at some point. While canker sores can occur at any age, they often first appear in adolescence and tend to decrease in frequency with age.

What are the symptoms of canker sores?

Common canker sore symptoms are as follows:

  • A canker sore on tongue might start with a tingling or burning sensation, signalling the arrival of the sore.
  • You'll notice a small, round or oval sore inside your mouth, typically on the inner cheeks, lips, tongue, or gums.
  • As it progresses, the canker sore becomes more noticeable, developing a white or yellowish centre surrounded by a red border.
  • Eating, drinking, and talking can become painful and challenging due to the sore's presence.
  • You might also experience a raw or rough feeling in the mouth, along with swelling or inflammation around the canker sore.
  • Sometimes, you might feel tired or generally unwell, although these systemic symptoms are less common.

What causes canker sores?

There are several canker sore causes that you should know about:

  • You may inherit a predisposition to developing canker sores, as they often run in families.
  • Accidental biting of the inner cheek, tongue, or lip, or irritation from dental appliances like braces, can trigger the formation of canker sores.
  • Your immune system might mistakenly attack healthy cells in the oral mucous membrane, causing a canker sore on lip or tongue.
  • High levels of stress or anxiety can weaken your immune system, making you more susceptible to canker sores.
  • Fluctuations in hormone levels, particularly during menstruation, pregnancy, or menopause, can increase the likelihood of canker sore outbreaks.
  • Certain foods and beverages, such as citrus fruits, spicy foods, and acidic drinks, can irritate the lining of your mouth and trigger canker sores.
  • A lack of essential nutrients like vitamin B12, zinc, folate, or iron in your diet can contribute to canker sore development.

How are canker sores diagnosed?

Here's a breakdown of how canker sores are diagnosed:

  • Your healthcare provider will visually inspect the inside of your mouth to look for characteristic canker sore symptoms. They will also examine the size, shape, and location of the sores.
  • Your doctor may ask about your medical history, including any previous occurrences of canker sores, family history of oral ulcers or any disease that you may have had.
  • Your healthcare provider may rule out other possible causes of oral ulcers, such as cold sores (caused by the herpes simplex virus), oral thrush (a fungal infection), or oral cancer.
  • In rare cases where the diagnosis is uncertain or if the canker sores are unusually large or persistent, a small tissue sample (biopsy) may be taken for further examination under a microscope.
  • In some instances, blood tests or other laboratory tests may be suggested to check for underlying medical conditions, such as vitamin deficiency, ulcerative colitis, AIDS, etc., that could be contributing to canker sore development.

How do you heal a canker sore fast?

Common canker sore treatment methods include:

  • Mix salt in warm water and rinse your mouth several times a day to reduce inflammation and promote healing.
  • To numb pain and speed up healing, apply over-the-counter topical ointments or gels containing ingredients like benzocaine or hydrogen peroxide directly to the sore.
  • Drink plenty of water to keep your mouth moist and aid in healing.
  • Brush gently with a soft-bristled toothbrush and avoid irritating the sore for quick canker sore treatment and healing.

How long do canker sores last?

Canker sores typically last between 7 to 10 days, although larger or more severe canker sores may take up to two weeks to heal.

Can I prevent canker sores?

Yes. You can easily prevent canker sores by practising the following habits:

  • Brush gently with a soft-bristled toothbrush and floss regularly to prevent irritation.
  • Opt for toothpaste and mouthwash that are free of harsh chemicals and abrasives, which can irritate oral tissues.
  • Steer clear of spicy, acidic, or rough foods that can trigger canker sores.
  • Practice meditation or yoga to minimize stress-induced canker sores.
  • Drink plenty of water to maintain your oral health.
  • Ensure you're getting enough essential nutrients like vitamin B12, zinc, and iron to support oral health.

What can I expect if I have a canker sore? 

You may wake up to soreness due to the canker sores and find it challenging to enjoy sour and spicy meals. Throughout the day, you have to apply home remedies. While canker sores are not contagious, they can recur and vary in frequency and severity from person to person.

What questions should I ask my doctor related to canker sore?

You can ask your doctor the following questions related to canker sores:

  • What could be causing my canker sores?
  • What treatment options are available for managing canker sores?
  • Are there any preventive measures I can take to reduce the frequency of outbreaks?
  • How can I effectively manage the pain and discomfort associated with canker sores?


In a nutshell, managing canker sores involves understanding their triggers, symptoms, and treatment options. By practising good oral hygiene, avoiding irritants, and managing stress, you can minimize outbreaks. Remember to consult a primary care doctor, a dentist, or dermatologist for personalized advice and treatment if needed. With proactive care, relief is attainable. If you are experiencing symptoms of canker sores and worried about any underlying medical problem that might be causing it, get yourself tested at Metropolis Healthcare for prompt and accurate diagnosis with no hidden charges. Metropolis Healthcare is the national frontrunner in pathology services with the sole aim of helping you know your health inside out. So do not wait; book a test today!

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