Sore mouth and throat during head and neck radiation

• Call 911 or go to an emergency department if your throat closes enough that you struggle to breathe, or you cannot swallow your own saliva. That is an airway problem, not a sore throat.
• Call your care team the same day if you feel as though you are choking, or you cough every time you eat or drink — NCI names both as throat changes to report.
• Call your care team the same day if you have stopped being able to take fluids at all. Radiation runs for weeks, and days without drinking is not something to push through alone.
• Call your care team within a day or two if your mouth hurts, your throat hurts, or you are losing weight. NCI says to tell them, because there are medicines that can help.

The inside of your mouth and throat is covered in a moist lining whose cells replace themselves rapidly. Radiation is hardest on cells that divide fast. That is the whole story in one sentence.

NCI's description of the resulting mouth problems includes mouth sores that are like little cuts or ulcers, dry mouth, taste loss, tooth decay, and thick, rope-like saliva.

For the throat, NCI says radiation therapy to the neck or chest can cause the lining of your throat to become swollen and sore, potentially creating difficulty swallowing.

This is expected, it is not a sign the treatment is going wrong, and it does not mean you should quietly endure it.

NCI also gives a rough shape to the throat problem. You may notice throat changes two to three weeks after starting radiation, and you will most likely feel better four to six weeks after radiation has finished.

People brace themselves for a dry mouth. Fewer people are warned about saliva that changes character.

Thick, rope-like saliva is genuinely unpleasant. It coats the mouth, it does not clear when you swallow, and it interferes with speech and eating in a different way from simple dryness. Tell your team if this is what you are dealing with, because it is a specific complaint with its own management rather than a variation of thirst.

NCI's food advice during radiation is to avoid sharp, crunchy foods, hot foods and spicy foods, and to avoid all tobacco products.

For a sore mouth generally, NCI's guidance is to choose foods that are soft, wet and easy to swallow, and to soften dry foods with gravy, sauce or other liquids.

That last suggestion is more useful than it sounds. Most of what you already eat can be made manageable by adding liquid. Bread becomes possible in soup. Meat becomes possible in sauce. You are not restricted to a short list of bland foods; you are adjusting the texture of what you already have.

Temperature matters too. Hot is on the avoid list, and many people find things easier at room temperature or cool.

NCI's instruction is direct: call your doctor or nurse when your mouth hurts. There are medicines and other products, such as mouth gels, that can help control mouth pain. For a sore throat it lists antacids, gels that coat the throat, and painkillers.

Raise this early in your course rather than waiting until you have not eaten properly for four days. Nutrition during radiation is not a side issue. Losing weight and strength midway through a six-week course affects everything else.

If eating is becoming genuinely difficult, ask about seeing a dietitian. Cancer centres have them, and they deal with exactly this.

NCI's advice is to check your mouth every day, watching for mouth sores, white patches or infection. Rinse every couple of hours with a salt water solution — its example is 1/4 teaspoon of baking soda and 1/4 teaspoon of salt in 1 quart of warm water. Brush your teeth, gums and tongue after every meal and at bedtime, using an extra-soft toothbrush, and skip any mouthwash containing alcohol.

The daily check matters because white spots can mean a fungal infection, which is a treatable problem on top of the radiation soreness rather than part of it.

Keep the routine gentle. A sore mouth is not the moment for vigorous brushing or alcohol-based mouthwash.

NCI is specific about timing. Visit a dentist at least two weeks before starting radiation therapy to your head or neck. The reason for the gap is practical: if you need dental work, it has to heal before radiation begins.

If your course has not started yet, book that appointment. Tooth decay, infections of the gums, teeth or tongue, and jaw stiffness and bone changes are all on NCI's list of what head and neck radiation can cause, and a dentist who knows your treatment plan is in a far better position to help you head those off.