When you go through radiation therapy to the head and neck area, at some point your mouth starts to burn. At first it feels like a minor sore spot, but by the second or third week of treatment, your tongue, gums, and the inside of your cheeks swell up red, and even swallowing your own saliva stings. This is radiation-induced oral mucositis. The mucosal cells react sensitively to radiation and break down and peel away, so it is absolutely not because you have been careless. That said, how you manage this period can make a real difference in how much it hurts and how fast you recover.
The first thing to watch is not irritating your mouth. Hot, spicy, or salty foods, sour fruit juice, carbonated drinks, and rough dry bread are harsh even on a healthy mouth, and to inflamed tissue they feel like a blade. Stick mostly to lukewarm, soft foods, but remember that eating too little and losing your strength is the bigger problem, so get your calories in somehow, whether through porridge, soft steamed egg, mashed tofu, or thin rice gruel with some protein mixed in. Alcohol and cigarettes are, needless to say, the main culprits that slow recovery.
If you give up on oral hygiene because it hurts, things only get worse. When bacteria settle into inflamed tissue, the inflammation worsens, and fungal infections easily pile on top. Brush gently with a soft-bristled toothbrush, and avoid commercial mouthwashes that contain alcohol, since the sting makes things more painful. Instead, dissolve half a teaspoon of salt and a little baking soda in a cup of warm water and rinse your mouth several times a day. It helps keep things clean without irritation. Once you try it, you can feel the difference.
If the pain is bad enough to interfere with eating, do not tough it out. Tell your care team. They can adjust things step by step, from a mouthwash that coats the mucosa, to a topical anesthetic preparation used before meals, to oral painkillers if needed. Enduring the pain blindly until you cannot eat leads to weight loss, which can affect your treatment schedule too, creating a vicious cycle. Dry mouth often comes along with it, so keep sipping small amounts of water, and using sugar-free gum or artificial saliva products makes it much more bearable.
Fortunately, radiation-induced oral mucositis usually improves on its own, with the mucosa gradually healing about two to four weeks after treatment ends. While you get through that rough patch, do not carry the pain all alone. If you develop a fever, a white film forms in your mouth, or the pain suddenly gets much worse, it could be a sign of infection, so report it quickly. This article is for general daily-care reference only; always consult your treating medical team about medication use or changes in your symptoms.