Mouth Sores: What They Are and What to Do

Do you have a painful mouth sore that makes it difficult to eat or speak normally? You're not alone. Mouth sores—also known as canker sores or oral ulcers—are small, round, and very bothersome lesions that appear on the oral mucosa. They are usually white or yellowish in the center, surrounded by a red, inflamed border, and can cause intense pain when touched. Fortunately, these mouth sores are not contagious and in most cases heal on their own within one or two weeks. In this article, we explain why mouth sores appear, how to heal a mouth sore quickly (including home remedies for mouth sores), and when it's advisable to see a dentist. Keep reading to learn why mouth sores appear and how to heal them as soon as possible and regain your well-being!

What are mouth sores? Are they the same as herpes?

A mouth sore is essentially a painful, superficial ulcer that appears on the soft tissues of the oral cavity (such as the inside of the cheeks, lips, tongue, or gums). The most common type of mouth sore is a canker sore, also called aphthous stomatitis or simply mouth ulcers. These lesions are characterized by being small (less than 1 cm), whitish or grayish in the center with a reddish halo, and by causing itching or burning, especially when eating acidic or spicy foods.

El NIDCR She clarifies that mouth ulcers are not contagious, unlike cold sores.

Types of mouth sores

When we talk about "mouth sores," we usually mean canker sores, but not all of them are the same. Here are the most common types:

Minor canker sores:

These are the most common. Small, round, and painful, they appear inside the mouth. They usually heal on their own in 1–2 weeks and do not leave a scar.

Major canker sores:

They are less common, larger, and deeper. They take longer to heal and can leave scars. If a sore doesn't improve within weeks, it's important to consult a professional.

Herpetiform aphthae:

They are many very small ulcers that come together to form a larger sore. They are painful, but they also heal in 1–2 weeks.

Herpes labialis:

Unlike canker sores, these lesions are contagious. They usually appear on the lips as blisters that later ulcerate and may require antiviral treatment. Avoid direct contact while they are active.

According to ColgateThe herpes simplex virus (HSV-1) is the main cause of cold sores, as distinct from canker sores.

Other ulcerative lesions:

There are mouth ulcers caused by fungi, bacteria, or autoimmune diseases. In rare cases, it can be something more serious. A warning sign: if a mouth ulcer lasts more than 2–3 weeks, it's best to see a dentist.

Symptoms of mouth sores and when to see a dentist?

Canker sores usually have obvious local symptoms: pain or burning in the area, discomfort when eating spicy, acidic, or very hot foods, and sometimes slight swelling around the sore. Unlike other injuries, canker sores don't usually cause fever or systemic symptoms. You simply feel uncomfortable because of the sore itself, but they generally don't cause malaise or other systemic discomfort.

When should you be concerned about a mouth sore? There are certain warning signs to watch out for when deciding whether to see a doctor or dentist about a mouth sore:

Why do mouth sores appear frequently? If you get mouth sores very often (more than 2-3 times a year), it is advisable to check for causes such as deficiencies or allergies.
If a sore lasts for more than 2 weeks without improving, you should go to the dentist to rule out anything more serious.
If the sore is accompanied by fever, malaise, swollen lymph nodes, or if many sores appear at once, seek medical attention.
If the pain is so severe that you can't eat or drink properly, a professional can help you manage it.

Home remedies for mouth sores

Minor canker sores usually heal on their own within 1–2 weeks, as the mouth regenerates quickly. There's no magic solution to make them disappear overnight, but there are ways to relieve the pain and help them heal a little faster if you're looking for simple ways to treat mouth sores.

At home, you can try several simple treatments. Rinsing with salt water is one of the most common: it cleans the sore and helps it heal, although it may sting a little on contact. You can also use baking soda, either as a rinse or a soft paste, to reduce irritation when a mouth sore appears.

Chamomile can soothe the area thanks to its anti-inflammatory properties; using a cool infusion as a rinse or applying the tea bag directly often provides relief. Aloe vera gel is also a great option for reducing inflammation and helping the wound heal, a common solution among home remedies for mouth sores and remedies that people use daily.

If the pain is intense, applying ice to the area can help numb and reduce swelling, but do so carefully. And don't forget to maintain good oral hygiene with a soft toothbrush to prevent the sore from becoming irritated or infected, and to help mouth sores heal faster.

These remedies are helpful and safe, but healing will take a few days. The important thing is to be consistent, avoid irritating the area, and be patient while the mouth sore heals completely. If you're wondering why mouth sores appear, it can be due to multiple factors such as stress, a weakened immune system, or minor injuries.

Medical treatments and antibiotic use

When mouth sores are very painful, very large, or slow to heal, it's time to consider medical treatment. To treat mouth sores more effectively, dentists and doctors may recommend:

Topical gels or creams:
Pharmacies offer topical medications (gels, ointments, rinses) specifically designed for canker sores. These typically contain local anesthetics (such as benzocaine or lidocaine) that numb the area and provide instant pain relief, or mild corticosteroids (like triamcinolone in dental adhesive) that reduce inflammation. There are also gels with hyaluronic acid that protect and accelerate the regeneration of the mucous membrane. These products are applied directly to the clean, dry sore, forming a protective film. They can speed up healing and provide relief for hours—ideal, especially before meals, so you can eat pain-free when you're looking for ways to treat a mouth sore.
Medicated mouthwashes:
If you have multiple or recurring mouth sores, a specially formulated mouthwash can be helpful. Sometimes doctors prescribe chlorhexidine gluconate rinses (a powerful antiseptic) to keep the area disinfected and prevent infection while they heal. Or, in more severe cases, corticosteroid rinses (such as dexamethasone) to reduce inflammation and pain. These treatments are used under professional guidance and for a limited time to help heal a mouth sore quickly.
Systemic oral medications:
Oral medications are only prescribed in special situations. For example, a short course of oral corticosteroids (such as prednisone) for large or multiple canker sores that don't respond to other treatments—this is rare and must be carefully evaluated by a doctor due to its potential side effects. Also, if a nutritional deficiency is identified (B12, folate, iron), you will be prescribed supplements to correct it and prevent the mouth sores from recurring.
Cauterization or laser:
Some clinics offer cauterization of the ulcer to accelerate its healing. This can be done with a chemical (silver nitrate) or a low-level laser. The goal is to superficially "burn" the ulcer tissue so it heals faster. It can provide almost immediate pain relief in many cases. However, this procedure should be performed by a professional; do not attempt dangerous home remedies.
Antibiotics for mouth sores?
Antibiotics are generally not needed for canker sores, as they are not caused by bacteria. Many people ask for antibiotics for mouth sores hoping for a quick fix, but the reality is that antibiotics won't help unless there is an underlying bacterial infection. If you notice any signs of infection, consult your dentist.

In most cases, home remedies and over-the-counter pharmacy products are enough to manage mouth sores until they heal. But if your mouth sores are severe or very frequent, your dentist can help with specialized treatments. It's always a good idea to consult a dentist if you're experiencing significant discomfort or if you're unsure why you're getting mouth sores.

Read also: Black gums: causes, treatment and how to lighten them

Conclusion

Mouth ulcers (canker sores) are a very common and annoying problem, but generally benign. We already know why mouth ulcers appear (from an accidental bite to stress) and also how to heal a mouth ulcer quickly with various home remedies and effective medical treatments.

The key is to stay calm: although it hurts, most will heal in a few days. Apply the tips mentioned to relieve pain and speed healing, and remember that if the mouth sore doesn't improve after two weeks, appears very frequently, or is accompanied by other symptoms, you should seek professional evaluation.

Do you need help with frequent mouth sores? Reservation Come in for an evaluation at our clinic and we'll help you find the cause and the best treatment.

Frequently asked questions about mouth sores

Why do mouth sores appear?

They usually appear due to minor scrapes or bites, stress, a weakened immune system, hormonal changes, or a vitamin deficiency. In most cases, they are not serious.

What are remedies for mouth sores used for?

They help relieve pain, reduce inflammation, and speed up healing so you can eat and speak without discomfort.

How to cure mouth sores?

You can use salt water rinses, special gels, aloe vera, chamomile, or ice. If there's no improvement in two weeks, it's best to consult your dentist.

What causes mouth sores?

The most common ones are caused by irritation, stress, allergies, low defenses, or minor traumas such as biting your cheek while eating.

What vitamin is lacking when mouth sores appear?

They are often associated with low levels of B vitamins, especially B12, as well as iron and folic acid.

What virus causes mouth sores?

Herpes simplex can cause painful sores or blisters around the lips. But common canker sores No. They are caused by a virus and are not contagious.