If you have a sore or dry mouth

Some cancer treatments can damage the cells that line your mouth or throat. Soreness and ulceration of the lining of the mouth or throat is called mucositis. It can be very painful. Mucositis can be caused by chemotherapy, targeted therapies, or radiotherapy to the head and neck. Any damage is usually temporary and most side effects go when treatment ends.

A common mouth infection called thrush (candidiasis) can cause the lining of your tongue and mouth to become red and swollen. It looks like white spots on your mouth and tongue. Thrush is treated with anti-fungal tablets. These tablets are also sometimes used to prevent thrush.

Your specialist nurse and doctor will talk to you about mouth care during treatment and they may examine your mouth. Tell them if your mouth is sore or if any soreness is getting worse.

Tips to keep your mouth healthy

The following tips may be helpful for keeping your mouth healthy during and after cancer treatment: 


  • Drink plenty of fluids, especially water. If you find that fresh fruit juices sting your mouth, try less acidic juices instead, such as peach or pear nectar, or blackcurrant or rosehip syrup. You could try freezing them in an ice-cube tray – sucking on the ice cubes can soothe your mouth.
  • Try milk or milk-based drinks, such as malted drinks, milkshakes and hot chocolate.
  • Cold foods and drinks may be more soothing. Try adding crushed ice to drinks and eating ice cream or soft, milk jellies.
  • Very hot or very cold drinks may irritate a sore mouth. Some people find drinks that are lukewarm or at room temperature more soothing.
  • Try drinking through a straw.


  • Avoid salty or spicy food.
  • Avoid rough-textured food like toast or raw vegetables. 
  • Keep your food moist by adding sauces and gravies.
  • Tell your doctor if you have a sore mouth. They can prescribe soothing or antiseptic lotions or sprays for you. 
  • You may find that taking painkillers before meals can help you swallow more easily.

Mouth care

  • Mouthwashes can be very soothing, but many of the ones available in chemists or shops may be too strong for you. Salt-water mouthwashes are just as effective at reducing soreness if it is not too severe. You can make this by adding a teaspoon of salt to cold or warm water. Rinse this around your mouth and then rinse with cold or warm water. Or your doctor can prescribe an anaesthetic gel or mouthwash instead. 
  • Many hospitals have their own mouth care guidelines for people having chemotherapy or radiotherapy, which include the best toothpaste to use. Your doctor or specialist nurse will be able to advise you. 
  • You may be advised to see your dentist before you start treatment. They may recommend using high-fluoride or non-foaming toothpaste to help reduce any soreness.
  • Use a children’s soft toothbrush to clean your teeth gently. Avoid using toothpicks when cleaning your teeth. If you want to use dental floss, check with your doctor or specialist nurse first. If you have a low platelet count, flossing can make your gums bleed. 
  • If you wear dentures, soak them in a denture-cleaning solution overnight. Leave them out for as long as you can during the day to prevent them rubbing against your gums.
  • If you are having radiotherapy to the jaw area, you may be advised to keep your dentures in as much as possible during the day to help maintain the shape of your gums. But if your mouth is very sore, it may be more comfortable to leave your dentures out.

Tips if you have a dry mouth

Radiotherapy to the head and neck area and some chemotherapy drugs can damage the saliva glands. This may lead to a dry mouth (xerostomia). The following tips may be helpful for coping with a dry mouth during and after cancer treatment.

  • If your tongue is ‘coated’, it may make your food taste unpleasant and might put you off eating. You can clean your tongue with a bicarbonate of soda solution. Use one teaspoon of bicarbonate of soda (available from your chemist) dissolved in a pint (570ml) of warm water. Clean your tongue with a soft toothbrush, foam-stick or gauze, dipped in the solution. Check with your clinical nurse specialist for more advice.
  • Frequent drinks, even if you just take a few sips at a time, can help keep your mouth moist. You may find fizzy drinks the most refreshing, including fizzy water. Keep a glass of water by your bed and carry water with you when you go out.
  • Try sucking ice cubes or lollies. You can make lollies by freezing fresh fruit juice in ice-cube trays or in lolly containers with sticks.
  • Keep your food moist by adding sauces and gravies.
  • Avoid chocolate and pastry, as they can stick to the roof of your mouth.
  • Chewing gum can sometimes stimulate the production of saliva.
  • Tell your doctor about your dry mouth. They can prescribe mouthwashes, lozenges, artificial saliva sprays or protective gels if needed.
  • It is important not to use any balm on your lips during radiotherapy treatment. Speak to your clinical nurse specialist or radiotherapy team about when you can use lip balm after treatment.
  • Try using an atomiser spray with cool water to keep your mouth moist.

We have information about mouth care during chemotherapy that you might find helpful.

I have a dry mouth and some foods have become very difficult to eat. The worst foods are bread and rice. Pasta is sort of okay, as long as there is lots of sauce.