Changes in your eating

Salivary gland cancer and its treatment can affect how you eat. There are ways to make it easier to cope.

Dry mouth

If you've only had surgery for your cancer, you might not notice a great deal of difference in how moist your mouth is. Your other salivary glands will make enough saliva to keep your mouth moist.

After radiotherapy to the head and neck area, a dry mouth can make eating and talking uncomfortable. Your doctor can prescribe artificial moisteners for your mouth if it is a problem for you. People who have a dry mouth often find it helps to sip water regularly and carry a bottle of water with them all the time.

As long as you’re making some saliva, drugs to stimulate your salivary glands might help. These include pilocarpine and bethanechol. The drugs have side effects and may cause sweating, blurred vision, or sickness. It might take up to 3 months for pilocarpine to work.

It's important to try to keep your mouth moist. A dry mouth can make you more likely to get an infection or tooth decay. Remember to have regular dental check ups.

Loss of taste

Radiotherapy and some chemotherapy drugs can affect your taste buds. So, if you have these treatments you may notice a change in how food tastes.

Some people say their food has a bitter, metallic or salty taste. Or that all food tastes the same. This usually improves over time but for a very few people it can be permanent.

Weight problems

Some people have lost weight when they are diagnosed with cancer. Pain when you are chewing or swallowing, can put you off eating. It can also be difficult to eat during treatment. Once treatment finishes you may need to build yourself up again. This can be difficult if you are still off your food.

Choose full fat versions of food such as milk and yoghurt rather than the low fat versions if you need to put on weight. You might also find that it helps to eat little and often, rather than trying to cope with a whole plateful in one go.

Liquid food

Your doctor can prescribe liquid food, which contains all the vitamins, proteins and carbohydrates you need for a balanced diet. They can also refer you to a dietician.

Sweating of the face when you eat

This is called Frey’s syndrome or gustatory sweating. It can happen after surgery to remove a parotid gland tumour. Between 5 and 50 out of 100 people (5 to 50%) have Frey’s syndrome after surgery.

When your surgeon removes the parotid gland they also cut the nerves in the area around it. As part of the healing process, the nerves that control saliva production sometimes link to the nerves that control sweating. This means that when you eat, rather than producing saliva you produce sweat. You might also feel warm and have some reddening on the affected side of the face.


For most people the sweating is very mild and doesn’t need treatment. Talk to your doctor if you do have it and you are finding it difficult to cope. There are treatments that can help including creams that you put on your face to help stop the sweating. Having botox injections put into the area might be able to help. You can have the injections more than once if they don't work or stop working. Very rarely your doctor might suggest surgery.

Difficulty opening the mouth due to a stiff jaw

Some types of surgery to the mouth can lead to a stiff jaw. It's also called trismus. This can make it difficult to open your mouth and so eating and drinking can be difficult.


Your dietitian and physiotherapist can help. They might suggest:

  • exercises to prevent your jaw becoming stiff
  • trying soft, moist foods with gravy or sauce
  • drinking through a straw

Other problems

After the first week, most people have very few problems. The problems you are likely to have depend on the treatment you have had.

Surgery to your mouth or jaw can cause pain and numbness in the area, which can make chewing difficult. You might not be able to move your lips very well which makes it difficult to keep food in your mouth when eating. Once you have healed and the pain has eased, you should be able to chew normally again. This usually takes about 4 weeks. Until then you might need to have a soft diet.

Problems with chewing may last longer if you have numbness from damage to the nerves in your head and neck. Some people need to have reconstructive surgery or a dental prosthesis put inside their mouth to help them chew and swallow. Your own surgeon is the best person to talk to about this if you are worried.

Last reviewed: 
04 Nov 2019
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