Why Do Mouth Ulcers (Canker Sores) Keep Coming Back? Causes, Prevention, and Treatment

Mouth ulcers, also called canker sores, are small, painful spots inside the mouth. Many people notice that these sores keep coming back. In fact, recurrent mouth ulcers can make eating and talking uncomfortable. This blog explains why mouth ulcers (canker sores) keep coming back, their causes, symptoms, and how you can prevent and treat them.

What Are Mouth Ulcers (Canker Sores)?

Mouth ulcers are open sores that form on the soft tissues inside your mouth. For example, they may appear on the inside of your cheeks, lips, or under your tongue. Unlike cold sores, mouth ulcers are not contagious. Most ulcers heal on their own within one to two weeks. However, some people get them often, which is called recurrent mouth ulcers.

Common Symptoms

Usually, mouth ulcers are easy to spot. Still, it helps to know the signs. Common symptoms include:

Small, round or oval sores with a white or yellow center

Red, swollen edges around the sore

Pain or burning, especially when eating or drinking

Sometimes, mild fever or swollen lymph nodes (rare)

Although most ulcers are harmless, they can be very uncomfortable.

Why Do Mouth Ulcers Keep Coming Back?

Many people wonder why their mouth ulcers keep returning. There are several causes and risk factors. Some of the most common reasons include:

Minor injuries: Accidentally biting your cheek or brushing too hard can trigger ulcers.

Stress: Emotional stress or anxiety can increase your risk.

Hormonal changes: For instance, some women get more ulcers during their period.

Food sensitivities: Spicy, acidic, or rough foods may cause sores in some people.

Nutritional deficiencies: Low levels of iron, vitamin B12, or folic acid can lead to recurrent mouth ulcers.

Medical conditions: Sometimes, diseases like celiac disease, Crohn’s disease, or a weak immune system can cause frequent ulcers.

Family history: If your parents had mouth ulcers, you may be more likely to get them too.

Because many factors can play a role, it is not always easy to find one clear cause.

Diagnosis and When to Seek Help

Most mouth ulcers do not need special tests. Usually, a dentist or doctor can diagnose them by looking at your mouth. However, you should seek help if:

Your ulcers last longer than two weeks

You have very large or painful sores

You get ulcers very often (more than three times a year)

You have other symptoms, like fever, rash, or trouble swallowing

Sometimes, blood tests or other exams may be needed to check for underlying health problems. According to the CDC, seeing a healthcare provider is important if you have frequent or severe mouth ulcers.

Effective Treatment Options

Although most mouth ulcers heal on their own, treatment can help reduce pain and speed up healing. Common treatment options include:

Over-the-counter gels or ointments: These can numb the area and protect the sore.

Saltwater rinses: Rinsing your mouth with warm salt water can help keep the area clean.

Pain relievers: Medicines like acetaminophen can ease discomfort.

Prescription treatments: In some cases, a doctor may suggest stronger medicines or mouth rinses.

However, you should avoid spicy or acidic foods until the sore heals. If you have frequent or severe ulcers, your doctor may check for other health issues.

Prevention Tips and Lifestyle Guidance

Preventing canker sores is possible for many people. Here are some helpful tips:

Brush your teeth gently with a soft-bristled toothbrush

Avoid foods that trigger your ulcers, such as spicy or acidic items

Eat a balanced diet rich in vitamins and minerals

Manage stress with relaxation techniques, like deep breathing or yoga

Drink plenty of water to keep your mouth moist

Visit your dentist regularly for check-ups

In addition, using toothpaste without sodium lauryl sulfate may help some people. These steps can lower your risk of recurrent mouth ulcers.

When to See a Dentist or Doctor

Although most mouth ulcers are not serious, you should see a dentist or doctor if:

Your ulcers are very large or painful

They last more than two weeks

You get them often or have other symptoms

Early care can help find and treat any underlying problems. The World Health Organization recommends seeking medical advice if you have frequent or severe mouth ulcers.

If you have frequent or severe mouth ulcers, consult a dentist for personalized advice and treatment options.