Mucositis causes inflammation and ulceration of the digestive tract lining. It usually affects the mouth and often results from cancer treatments.

When the thin mucous membrane that lines the digestive tract becomes inflamed, it can be painful. This condition, mucositis, can develop anywhere along the digestive tract, but it is common in the mouth.

People who undergo cancer treatments, such as chemotherapy, have a high risk of developing this condition.

Below, we discuss the symptoms and causes of mucositis, as well as the treatment options.

Mucositis can cause a range of symptoms, many of which affect the mouth. Some common symptoms of mucositis include:

  • dry mouth
  • thickening of the saliva
  • an increased amount of mucus
  • shiny, swollen, or red gums
  • soft, white patches or pus on the tongue
  • sores in the mouth
  • blood in the mouth
  • pain or a mild burning sensation while eating
  • trouble swallowing or talking

In very severe cases, mucus, pus, or thick saliva can fill the mouth. If this occurs, it can prevent a person from eating.

Cancer treatments are a common cause of mucositis. Whether or not they are targeting cancer, the following treatments frequently cause mucositis:

  • chemotherapy
  • radiation of the head, chest, or neck
  • bone marrow transplants
  • stem cell transplants

The cells in the body’s mucous membranes divide rapidly, similar to cancer cells. Chemotherapy and radiation therapy attack cancer cells and any other rapidly dividing cells, including those of the mucous membranes.

Around 40% of people who receive chemotherapy may develop mucositis to some extent. The risk is likely greater for people who also receive radiation therapy on the head, neck, or chest.

Several factors can also increase the risk of mucositis. They include:

  • being female
  • having received cancer treatment
  • experiencing dry mouth before and during cancer treatment
  • being dehydrated
  • having a chronic condition, such as kidney disease or diabetes
  • having an unusually low body mass index
  • having poor oral health
  • chewing or smoking tobacco
  • drinking alcohol

There are several potential complications of mucositis. A person may, for example, lose their appetite for food and drink.

Also, mucositis can increase the risk of bacterial, viral, or fungal infection. A particular risk is septicemia, a bacterial infection of the blood.

Meanwhile, receiving treatment for mucositis can delay cancer treatments or cause additional side effects.

Many cancer treatments affect the immune system, which is the body’s defense against infections. As a result of this, cancer treatments can delay recovery from mucositis.

If mucositis symptoms make it difficult to eat or drink, nutrient deficiencies can develop. Someone undergoing cancer treatment may already have difficulty eating, so any additional challenges are especially concerning.

Symptoms of mucositis are often clear in the early stages of cancer treatment. A doctor may be able to diagnose mucositis as early as 1–2 weeks after radiation therapy or within 3 days of chemotherapy.

First, the doctor will assess the person’s symptoms and medical history. They will then ask about past or ongoing cancer treatment and examine the affected area. They may, for example, look for sores and swelling in the mouth.

Treatment usually involves targeting the infection while managing symptoms.

To reduce symptoms, including pain, the doctor may recommend:

  • ice chips, popsicles, and other cold foods
  • topical pain relief medications
  • allergy medications
  • lozenges
  • corticosteroids
  • sprays for preventing dry mouth

To treat the infection, the doctor might suggest:

  • brushing the teeth more frequently each day
  • brushing with a soft toothbrush
  • using antiseptic mouthwash

It is not always possible to prevent mucositis. However, a person can take some steps to reduce their risk.

Oral hygiene is an important element in the prevention of mucositis. A person’s oral hygiene routine should include:

  • brushing the teeth regularly
  • using a toothpaste that contains fluoride
  • going for frequent dental checkups
  • using dental floss or interdental brushes to clean between the teeth
  • regularly using mouthwash or gargling with a saltwater solution
  • making sure any dental fixtures fit well

Other preventive measures include:

  • avoiding all tobacco products
  • staying hydrated
  • keeping the lips and mouth moist
  • eating a healthy, balanced diet
  • avoiding hot, spicy, or salty foods
  • limiting the intake of hot, fizzy, or alcoholic drinks
  • avoiding hard or crunchy foods
  • lowering the sugar intake

Mucositis can cause pain, discomfort, and difficulty eating.

The infection is common among people undergoing cancer treatment, such as chemotherapy or radiation therapy.

Anyone with mucositis should see a doctor, who will recommend treatments to relieve pain and help keep the area moist.

To reduce the risk of mucositis, maintain good oral hygiene and avoid certain foods and drinks, such as those that are hot, spicy, or alcoholic.