Mouth sores can have various causes, including canker sores, infections and pressure ulcers due to dentures. One common cause is cancer treatment: It can attack the mucous membranes or weaken the immune system so much that germs spread and lead to inflammations.
Various treatments are used depending on the cause. For example, antimycotics (antifungal drugs) are a suitable treatment for a fungal infection. There aren’t always special medications that can get rid of the underlying cause, though. Then you can use creams or gels from the pharmacy that relieve or slightly numb the pain.
If you would prefer not to use medication, you can try to protect the lining of your mouth when you eat and drink.
What foods and drinks should I avoid?
To keep from irritating inflamed parts of your mouth more, and to prevent them from getting worse or new sores from forming, it’s better to avoid the following foods and drinks until the wounds have healed:
Carbonated ("fizzy") drinks
Hot foods and drinks
Very spicy foods
Acidic foods like tomatoes or citrus fruits
Hard and sharp-edged foods like bread rolls, raw vegetables or chips (crisps)
What should I consider when preparing meals?
When you chew, the mucous membranes lining your mouth move. This stretches the sore areas, which can hurt. Eating soups or soft food can help to prevent this pain.
During cancer treatment, people may have inflammations in their mouth as well as nausea, loss of appetite or loss of taste. As a result, they may eat less and lose too much weight. Adding things like butter or cream to soups and puréed food may help. This keeps the meals easy to eat and ensures that you have more calories even when you eat smaller portions. The higher fat content also enhances the taste of the food, making it easier to avoid using a lot of spices.
It is also important to let cooked food cool down enough before you eat – or to simply eat cool meals. There are various dishes that taste good despite being cold – like savory soups made with buttermilk, or sweet foods like custard, mild quark cheese, yogurts or shakes. If you like it sweeter, you could add honey instead of sugar or eat a spoonful of pure honey every now and then. Some studies have shown that honey helps to relieve the pain caused by inflammations of the membranes lining the mouth in people who have cancer.
Keep up oral hygiene
Thorough oral and dental hygiene is important – not only to prevent inflammations in the mouth, but also when mouth sores have already developed. This means:
Brushing your teeth after meals and before going to bed with a soft brush
Rinsing your toothbrush carefully after brushing, letting it dry and replacing it regularly (every month)
Cleaning dentures and wearing them less for as long as the inflammation lasts
Cleaning the spaces between your teeth as you usually do, for instance with special interdental brushes (but if that's not part of your normal routine, you shouldn't start when you have an acute inflammation)
Using non-alcoholic mouthwashes
What else is important?
It is also important to drink enough fluids, not smoke and regularly check the lining of your mouth in the mirror. If the pain gets worse, or if the mucous membranes swell, change color or bleed heavily, it's a good idea to see a doctor or dentist.
IQWiG health information is written with the aim of helping people understand the advantages and disadvantages of the main treatment options and health care services.
Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.
Our information is based on the results of good-quality studies. It is written by a team of health care professionals, scientists and editors, and reviewed by external experts. You can find a detailed description of how our health information is produced and updated in our methods.
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