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Mouth care

This leaflet is for people who are at risk of developing mouth problems such as dry mouth, thrush infection of the mouth (oral thrush), bad breath, inflammation and mouth ulcers. This includes people who are unwell with serious illness, or who are having chemotherapy or radiotherapy. Good mouth care can prevent some problems from developing, or prevent minor problems from getting worse.

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How to take care of your mouth

If you are at risk of developing mouth problems, try to do the following either yourself or with the help of a carer to keep your mouth clean:

  • Brush your teeth twice a day using toothbrush with soft bristles and fluoride toothpaste. This will help prevent tooth decay.

  • Rinse your mouth after meals and at night. Use water or 0.9% sodium chloride solution (saline or salt water). You can make a fresh sodium chloride solution for each rinse by dissolving half a teaspoon of salt in 250 ml of fresh water. Use cool or warm water - whatever your prefer.

  • Remove any debris that you can see in your mouth or on your tongue by gentle brushing with a soft toothbrush. If possible, do this regularly but mainly after meals and at bedtime. Foam sticks are an alternative if gentle brushing with a soft toothbrush causes pain or bleeding.

  • Chewing pineapple may also help to clean your mouth. Pineapple contains ananase which is an enzyme (chemical) which may help to break down debris in the mouth. You can use fresh pineapple or unsweetened tinned pineapple.

  • If you wear dentures, remove them at night. Clean dentures with a soft toothbrush and toothpaste. Soak overnight in a denture solution containing sodium hypochlorite. Rinse before use the next day. (Soak metal dentures in chlorhexidine solution.)

If you have a very high risk of developing mouth problems (for example, if you have radiotherapy to the head or neck), it is best to increase the frequency of the measures above. For example, rinse your mouth every 1-2 hours.

More about mouthwashes

  • Water or saline (described above) are the most commonly used mouthwashes. They are soothing, do no harm, and are safe to use as often as you like.

  • Chlorhexidine mouthwash is sometimes advised if you are at risk of mouth infection. However, you should not normally use this more than twice a day. It contains alcohol which may sting, especially if your mouth is inflamed. If you do use this twice a day, you can always use water or sodium chloride mouthwashes as often as you like in between.

  • Other mouthwashes such as ascorbic acid solution, hydrogen peroxide mouthwash or sodium bicarbonate mouthwash may be advised by a doctor or nurse in certain circumstances.

  • It is best not to use glycerine or lemon mouthwashes. They often increase the sensation of a dry mouth.

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Some mouth problems that may occur if you are unwell

Dry mouth

Dry mouth has various causes. Simple measures such as drinking frequent sips of water and chewing sugar-free gum will often help. This may be all that is needed in many cases. Artificial saliva or medicine to stimulate the salivary glands is sometimes used. See the separate leaflet called Dry Mouth for more details.

Oral thrush (oral candida)

Thrush is an infection caused by a yeast germ called candida. Small numbers of candida commonly live in a healthy mouth. They are usually harmless. However, certain situations may cause an overgrowth of candida which may lead to a bout of oral thrush. These include a dry mouth, and if you are in general poor health or have an immune system which does not work as well as it should. The classical symptom is for white spots to develop in the mouth. However, sometimes there are no white spots and areas within the mouth may just become red and sore. Most cases are treated with drops, lozenges or a gel which contains an anti-thrush medicine such as nystatin, amphotericin or miconazole. Anti-thrush tablets such as fluconazole are sometimes used. See the separate leaflet called Oral Thrush (Yeast Infection) for more details.

Mouth ulcers

Aphthous mouth ulcers are the most common type. They are painful, and can return from time to time. Each bout of ulcers usually goes away in time without treatment. Mouthwashes and steroid lozenges may ease the pain, and may help the ulcers to heal more quickly. See the separate leaflet called Mouth Ulcers for more details.

Other types of mouth ulcer sometimes develop. Your doctor will advise on treatment.

Bad breath (halitosis)

In most cases of persistent bad breath, the smell comes from a build-up of germs (bacteria) within the mouth - in food debris, plaque and gum disease, or in a coating on the back of the tongue. Good oral hygiene will often solve the problem. That is, routine oral care described above, and in addition (if possible) regular flossing, scraping the back of the tongue, and antiseptic mouthwashes. See the separate leaflet called Bad Breath (Halitosis) for more details.

Other causes of bad breath may develop in people who are unwell. For example, oral thrush, a dry mouth, and tumours in the mouth can cause bad breath. If these can be treated then this may clear the bad breath.

Oral mucositis

Mucositis is a painful inflammation and ulceration of the lining of the mouth (the mucous membranes). Mucositis is a common side-effect of chemotherapy and radiotherapy, especially radiotherapy that involves the head and neck. It occurs because the rapidly dividing cells on the inside lining of the mouth are affected by the treatment that is directed at the rapidly dividing cancer cells. Mucositis tends to get better 2-3 weeks after the course of chemotherapy or radiotherapy treatment has finished. However, whilst you have mucositis you are more prone to develop other mouth problems such as infection and dry mouth. The routine mouth care described above before, during and after treatment reduces the severity of mucositis, and helps prevent secondary infection. Treatment for pain, dry mouth and infection may also be needed.

Mouth pain

There are many different causes of mouth pain. Sometimes the pain is localised to one area. Sometimes it is more generalised inside the mouth. Treatment depends on the cause and may include:

  • Treating the underlying cause (if possible).

  • Local anaesthetic sprays, painkilling tablets, and locally applied painkilling gels and mouthwashes.

Your doctor will be able to advise on some mouth issues, but doctors are not trained to look after teeth or gums and so if you think that the issue is to do with your teeth or gums, see a dentist and do not contact your GP for advice.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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