Nutritional tips for thickened secretions forming in mouth and throat during cancer treatment

Thick and excessive secretions forming in the mouth or throat is a side effect that can often occur during or after radiation to the head and neck, oesophagus, and lungs.

The thick secretion can be difficult to manage and may contribute to difficulty in swallowing, nausea, vomiting, or poor oral health.

With very thick secretions forming in the mouth, it can help if you use a nebuliser or oral rinses. You can find these online or from the pharmacy. It may also be worth trying to remove the secretions from your mouth before eating. Some patients find that leaning over a steaming bowl of hot water with a towel over their head helps to loosen thick, sticky saliva.

The following nutritional tips might help to reduce secretion build up in the mouth.

Choose sour-tasting food and drinks

Eating sour food may help make the saliva in your mouth more watery. This may help reduce the formation of thickened secretions mucus. Sour foods include pineapple, pickles, cucumber, apple, kiwi, seedless grapes, tangerines, oranges, and tomatoes. Sauces such as piccalilli, tomato ketchup, and vinegar-based dressings can also help create watery saliva.

However, eating or drinking these acidic foods may cause some discomfort if your mouth is very sensitive or sore. If that’s the case, you should avoid sour food and drinks.

Keep well hydrated

Making sure that you drink enough fluid is important as this will prevent dehydration and may help thin the thickened secretions. If your intake of fluids is limited or weight loss is a concern, you can increase your intake of protein and energy-rich fluids, such as fortified milk and milkshakes. A dietitian will be able to advise you on the best sources for you.

Rinse your mouth after drinking milk

Milk is not the cause of thickened secretion formation, but it can leave a sticky feeling in your mouth. After drinking milk rinse your mouth with water. Sour milk products such as buttermilk and yoghurt drinks feel less sticky. Products made from boiled milk such as custard may also feel less sticky in the mouth. Sometimes soy, almond or oatmeal drinks are good alternatives to regular milk.

However, keep in mind that these drinks may not contain added calcium and vitamin D or equivalent protein – check the label to see if it has been fortified.

Spray or rinse your mouth with a saline solution

By spraying or rinsing your mouth with a saline solution, you can dissolve some of the thickened secretions in your mouth. You can make a saline solution by adding two small teaspoons of table salt to a litre of lukewarm water. Prepare a new solution every day. You can buy empty spray bottles at the pharmacy to fill with the saline solution for easy spraying at home and on the go.

Ask a dental hygienist for advice

A dental check-up may be able to guide you on the best way to manage these symptoms and give you practical tips for taking care of your mouth.

Get more advice on mouth issues during cancer treatment

> Nutritional tips for a soft textured diet during cancer treatment

> What can I do if I have a dry mouth during cancer treatment?

> Nutritional tips for a sore mouth

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