Sore mouth and throat
Sore mouth and throat can include redness, swelling and painful sores on the tongue, gums, lips or throat. Sore mouth may also be called oral
Sore mouth and throat can be caused by chemotherapy or radiation therapy. The cells that line the inside of the mouth and throat divide quickly, making them sensitive to the effects of these cancer treatments. When the cells are damaged, the lining of the mouth and throat becomes inflamed (red and swollen). If the damaged cells can't repair themselves, sores can develop. When the lining of the mouth and throat is injured, it can lead to infections.
The following side effects of cancer treatment can increase your chance of developing a sore mouth and throat:
Many chemotherapy drugs can cause a sore mouth and throat. This is more likely to happen when higher doses or many frequent doses are given. Sore mouth and throat is usually worse when chemotherapy is given with radiation therapy. If you have a very sore mouth and throat, the dose of chemotherapy may have to be lowered or stopped temporarily to give your body time to heal.
Sore mouth and throat often happen with the following chemotherapy drugs:
high-dose melphalan (Alkeran)
BEAM chemotherapy regimen – carmustine (BiCNU), etoposide (Vepesid), cytarabine and melphalan
Sore mouth and throat caused by chemotherapy will usually heal about 2 to 4 weeks after your treatment is finished, if there is no infection.
Radiation therapy @(Model.HeadingTag)>
Radiation therapy to the head and neck can cause a sore mouth and throat. The likelihood of developing a sore mouth and throat and how severe it is are related to the number of treatments and the amount of radiation you receive.
Sore mouth and throat caused by radiation therapy usually lasts about 6 to 8 weeks after your treatment ends, depending on how long it was.
Stem cell transplant @(Model.HeadingTag)>
The conditioning therapy given before a stem cell transplant can cause severe sore mouth and throat. This therapy includes high doses of chemotherapy and sometimes radiation to the whole body (called total body irradiation or TBI). You are more likely to develop a sore mouth and throat, and it can be worse, if you have both chemotherapy and TBI.
Sore mouth and throat is more severe and lasts longer with an allogeneic stem cell transplant (the cells come from a donor) than with an autologous stem cell transplant (the cells are your own).
People undergoing a stem cell transplant have a weakened immune system and so cannot fight infections very well. This puts them at high risk of developing a systemic infection if they have sores in their mouth or throat.
Sore mouth and throat related to a stem cell transplant usually lasts for about 2 weeks after the conditioning treatment ends.
Graft-versus-host disease @(Model.HeadingTag)>
Graft-versus-host disease (GVHD) is a side effect that can happen if you have an allogeneic stem cell transplant. It causes damage to your tissues and organs. Sometimes it can affect your mouth, which is called oral GVHD. Sores usually happen on the inner lining of the cheeks and lips and the sides of the tongue.
Other factors @(Model.HeadingTag)>
Other factors can increase your risk of developing a sore mouth and throat:
- drinking alcohol'
- poor oral hygiene
- poorly fitting dentures
- gum disease
- poor nutrition
- overgrowth of micro-organisms in your mouth
Symptoms of sore mouth and throat can vary depending on their cause and other factors. Symptoms include:
- sores (ulcers)
- trouble eating and drinking
The pain from a sore mouth and throat can range from mild to severe. It can make eating, drinking and swallowing painful and affect your
Check your mouth, gums and tongue daily for any signs of mouth sores. Notify your healthcare team of any changes. Mouth sores put you at risk of developing an infection. Symptoms of a mouth infection include white spots or a white coating inside your mouth or on your tongue.
Your doctor will do an oral exam to check your mouth and throat and diagnose any infections.
Preventing sore mouth and throat @(Model.HeadingTag)>
If you have a high risk of developing sore mouth and throat, prevention is the best strategy. Talk to your healthcare team about the following.
Oral care plan @(Model.HeadingTag)>
Taking care of your mouth and teeth while you are receiving cancer treatment helps lower your chance of developing a sore mouth and throat and related infections.
Your healthcare team may give you an oral care plan. This is a set of instructions that will tell you how to care for your mouth and teeth while receiving cancer treatment. Your healthcare team will adjust your oral care plan if you develop a sore mouth and throat or mouth infection.
These are general tips for rinsing your mouth:
Use the following recommended rinsing solution: 1 teaspoon salt, 1 teaspoon baking soda and 1 litre water.
- Prepare the rinse fresh each day and do not refrigerate it.
- Rinse your mouth before and after every meal and at bedtime.
These are general tips for cleaning your mouth:
Rinse your toothbrush in hot water to soften it before brushing.
- Use a very (ultra) soft toothbrush with a round head.
- Clean your teeth and mouth within 30 minutes after eating and before bed.
- Gently brush your tongue from back to front.
- Rinse your toothbrush in hot water after each use and store it in a clean, dry place.
- Ask your healthcare team about flossing. It may not be recommended if you haven't flossed regularly.
- Remove your dentures for at least 8 hours and soak them in the rinsing solution.
Cryotherapy is also known as cold therapy. Keeping your mouth cold during chemotherapy with certain drugs can help prevent or reduce the severity of a sore mouth and throat. Usually you hold or swish ice chips in your mouth for a few minutes before and during your treatment.
Cold therapy is most beneficial for people receiving
Your healthcare team may suggest the following medicines to help prevent a sore mouth and throat:
benzydamine mouthwash (Pharixia) – for rinsing your mouth and gargling
- glutamine – a natural supplement taken by mouth for people receiving radiation therapy and chemotherapy for head and neck cancer
Light or laser therapy @(Model.HeadingTag)>
Some people with cancer may be offered light or laser therapy (called photobiomodulation) to help prevent sore mouth and throat and related pain. It uses low doses of light to treat the inside of your mouth. You may receive this therapy if you have:
a stem cell transplant
- radiation therapy, with or without chemotherapy, for head and neck cancer
Light or laser therapy is a newer treatment and might not be available at all cancer treatment centres.
Preventing infections @(Model.HeadingTag)>
Following your mouth care plan is the best way to prevent infections in your mouth and throat. Your healthcare team may also prescribe medicines to help prevent infections. Fluconazole (Diflucan) is helpful in preventing thrush (oral candidiasis), which is caused by a common
Managing sore mouth and throat @(Model.HeadingTag)>
Your healthcare team may suggest the following ways to manage your sore mouth and throat and help it heal.
Practise good oral hygiene @(Model.HeadingTag)>
If you develop a sore mouth and throat, your healthcare team will update your oral care plan as needed. This may include rinsing more often, not flossing your teeth or not wearing your dentures. Your healthcare team will give you instructions about cleaning and rinsing your mouth and what to use.
Maintain good nutrition @(Model.HeadingTag)>
A sore mouth and throat can make it hard to eat. A registered dietitian can suggest ways to help you maintain good nutrition if eating is hard for you. You can try the following tips if you have a sore mouth and throat:
Drink plenty of liquids, like broth, water or milk.
- Choose soft, moist, smooth foods that are easy to chew and swallow.
- Cut or mash foods into small pieces or use a blender to puree foods.
- Cook foods until soft.
- Add sauces to moisten food.
- Choose soft foods and nourishing liquids that are high in calories and protein.
- Avoid foods that irritate your mouth and throat, such as acidic, salty and spicy foods.
- Eat foods lukewarm or at room temperature if hot or cold foods hurt your mouth.
- Avoid rough and dry foods with sharp edges, such as raw vegetables, toast, potato chips, pretzels and nuts.
- Avoid alcohol and alcohol-based mouth rinses.
For more tips and information, check out eating well.
Use pain medicine @(Model.HeadingTag)>
Pain relief is important because a sore mouth and throat can make it hard to eat and can lead to unintentional weight loss. Weight loss can weaken the immune system, affect how wounds heal and make you tired and uncomfortable. During cancer treatment, you need to stay well nourished to help keep your body strong and to heal faster. Your healthcare team will recommend or prescribe pain-relieving medicines that are right for you. Do not take any over-the-counter pain relievers without checking with your healthcare team first.
Medicated mouth rinses can be used to treat pain from a sore mouth and throat. They may make it more comfortable to eat and drink.
Opioid pain medicines can make it more comfortable to eat, drink and brush your teeth. It's best to take the medicine 1 hour before eating or brushing your teeth to give it time to work. Opioids may also be given as a transdermal patch that you stick on your skin. People receiving a stem cell transplant will usually be given intravenous (IV) opioid pain medicine.
Treat infections @(Model.HeadingTag)>
Your healthcare team will prescribe medicines to treat infections in your mouth and throat. It's important to treat these infections before they enter the blood and become serious.
Fungal infections @(Model.HeadingTag)>
Thrush (oral candidiasis) is a common fungal infection in the mouth. It often causes white patches or a white coating in the mouth and on the tongue. Topical antifungal medicines are usually used to treat a mild case of thrush. These medicines can be given as:
- mouth rinse
If you wear dentures, you may be told to soak them overnight in the mouth rinse or to use an antifungal cream on them.
Treatment for moderate to severe fungal infections may also include oral antifungal medicines.
Bacterial infections @(Model.HeadingTag)>
Many different types of bacteria can cause mouth infections. Treatment for bacterial infections may include oral antibiotics.
Feeding tubes and parenteral nutrition @(Model.HeadingTag)>
Some people will develop a severe sore mouth and throat during their cancer treatment and will not be able to eat. This is very common in people who receive both chemotherapy and radiation therapy for head and neck cancer.
If you can't eat, you will need a feeding tube or total parenteral nutrition (TPN) to provide your body with enough nutrition. A feeding tube is inserted through the skin of the abdomen into the stomach (called a gastrostomy tube) or into the small intestine (called a jejunostomy tube). Parenteral nutrition delivers nutrients directly into your bloodstream through an IV catheter.
You can start eating by mouth again when your cancer treatment is finished and your mouth and throat are healed.
Bethany Boutilier, RD
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