1. Are canker sores contagious?

No, they are not contagious. They are not caused by viruses or bacteria but are typically linked to other factors like stress or injuries.

2. What’s the difference between canker sores and cold sores?

Canker sores occur inside the mouth and are not contagious, while cold sores usually appear outside the mouth and are caused by the herpes simplex virus (HSV).

3. How long do canker sores last?

Most of the time heal within 1–2 weeks without treatment. Severe or larger sores may take longer.

4. Can certain foods trigger canker sores?

Yes, spicy, acidic, or salty foods can irritate the mouth lining and contribute to its development.

5. Should I see a dentist or doctor for canker sores?

If you have frequent, severe, or unusually large sores that don’t heal within two weeks, consult a dentist to rule out underlying conditions.

6. Can canker sores indicate an underlying health problem?

Recurrent outbreaks may signal conditions like celiac disease, Crohn’s disease, or a weakened immune system. A healthcare professional can provide a proper diagnosis.

7. Can children get canker sores?

Yes, children can develop them, especially if they experience stress, have poor oral hygiene, or accidentally injure their mouths.

8. Does toothpaste cause canker sores?

Toothpaste containing sodium lauryl sulfate (SLS) can irritate the mouth lining and increase the risk of outbreaks. Switching to an SLS-free toothpaste may help.

9. How can I reduce pain from canker sores quickly?

Applying topical gels, rinsing with salt water, and avoiding spicy or acidic foods can provide quick relief.

Canker Sores 🦷🔥: Causes, Symptoms, Treatments, and Prevention

Canker sores, also known as aphthous ulcers, are small, painful lesions that develop inside the mouth. Unlike cold sores, they are not contagious. These ulcers can make eating, drinking, and talking uncomfortable.

Understanding their causes, symptoms, and treatment options can help manage and prevent future outbreaks.

Table of content

Causes of Canker Sores 🧬

The exact cause of canker sores remains unclear, but several factors may contribute to their development:

Injury to the mouth: Accidental cheek bites, dental work, or aggressive brushing.
Food sensitivities: Particularly to acidic or spicy foods.
Nutritional deficiencies: Lack of vitamin B-12, zinc, folate, or iron.
Allergic responses: To certain bacteria in the mouth.
Hormonal shifts: Especially during menstruation.
Emotional stress: High stress levels can trigger outbreaks.
Medical conditions: Such as celiac disease or Crohn’s disease.

Symptoms 🔍

Canker sores typically present with the following signs:

Painful sores: Small, round or oval ulcers with a white or yellow center and a red border.
Tingling or burning sensation: Often precedes the appearance of the sores.
Discomfort: While eating, drinking, or speaking.
Swelling: In the affected area.

In severe cases, individuals may experience:

Fever 🤒
Physical sluggishness 😴
Swollen lymph nodes 🦠

Treatment Options 💊

While canker sores usually heal on their own within 1 to 2 weeks, certain treatments can alleviate discomfort:

Over-the-counter topical products: Such as benzocaine or hydrogen peroxide rinses.
Mouth rinses: Containing dexamethasone or lidocaine to reduce pain and inflammation.
Nutritional supplements: If deficiencies are identified.
Avoiding irritants: Such as spicy or acidic foods.
Maintaining oral hygiene: Using a soft-bristled toothbrush and avoiding toothpaste with sodium lauryl sulfate.

Prevention Strategies 🛡️

To minimize the occurrence of canker sores:

Monitor your diet: Avoid foods that irritate your mouth.
Maintain good oral hygiene: Brush and floss regularly.
Manage stress: Incorporate relaxation techniques into your routine.
Protect your mouth: Use orthodontic waxes if you have braces.
Stay hydrated: Drink plenty of water throughout the day.

FAQs ❓

Are canker sores contagious?
No, canker sores are not contagious and cannot be spread through kissing or sharing utensils.

How long do canker sores last?
Most canker sores heal within 1 to 2 weeks without treatment.

When should I see a doctor?
If sores are unusually large, persist beyond two weeks, or are accompanied by high fever, consult a healthcare professional.

Can children get canker sores?
Yes, children can develop canker sores, often due to mouth injuries or stress.

Do certain foods trigger canker sores?
Yes, acidic, spicy, or salty foods can trigger or worsen canker sores in some individuals.

Conclusion 🎯

Canker sores, though harmless, can disrupt your daily routine with pain and discomfort.

By understanding their causes, recognizing triggers, and taking steps to prevent them, you can reduce their occurrence and impact.

If you experience frequent or severe outbreaks, consult a healthcare professional for personalized advice.

Maintaining a healthy lifestyle and good oral hygiene can go a long way in keeping your mouth healthy and free of sores.

References

InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. Overview: Canker sores (mouth ulcers) [Updated 2022 Oct 17]. Available from: https://www.ncbi.nlm.nih.gov/books/NBK546250/
Plewa MC, Chatterjee K. Recurrent Aphthous Stomatitis. [Updated 2023 Nov 13]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK431059/