Stomatitis After Chemotherapy: Oral Care Tips

Dr. Boris Wydoff

Stomatitis after chemotherapy is an unpleasant complication that can make eating, drinking, and even talking difficult. What should you do right now? Clean your mouth gently with a soft toothbrush, keep the mucosa moist, choose soft foods, and let your oncologist know about any sores or pain that appear. You don't have to endure significant discomfort: there are ways to ease your condition.

Why Does Stomatitis Appear After Chemotherapy?

Stomatitis is an inflammation of the oral mucosa. Following anti-tumor treatment, doctors frequently observe a condition known as oral mucositis. It is linked to damage to the cells of the mucous membrane and can affect the inside of the cheeks, gums, tongue, lips, and throat.

A person may notice redness, soreness, a burning sensation, or small sores. Sometimes swelling and increased sensitivity to hot and cold foods occur. In severe cases, chewing, swallowing, and even drinking plain water becomes difficult.

The mucosa may look irritated, with painful areas and whitish patches developing. Taste perception changes: familiar foods may seem bland, bitter, or acquire a metallic taste. Some people also experience dry mouth.

Chemotherapy affects more than just cancer cells. Certain medications also damage healthy cells, including those that make up the lining of the oral cavity. Therefore, stomatitis can develop even in someone who meticulously cared for their teeth and gums before treatment began.

Such complications do not happen to everyone. Their severity depends on the anti-tumor drugs used and the specifics of the treatment. Sometimes unpleasant sensations begin a few days or weeks after therapy starts and gradually fade after it ends. However, certain issues may persist longer.

How to Know It Is Stomatitis and Not Another Problem?

Mouth stomatitis after chemotherapy can manifest in various ways. In one person, redness and burning predominate; in another, painful sores appear; in a third, the main complaint is dryness and an unpleasant taste.

For example, stomatitis on the tongue after chemotherapy may be accompanied by soreness when talking and eating. Sometimes the surface of the tongue becomes especially sensitive to acidic, salty, or hot foods. If changes affect the inside of the cheeks, a person may feel pain even during normal mouth movements.

Aphthous stomatitis after chemotherapy deserves a separate mention. Aphthae are small, rounded sores with a whitish or yellowish center and a reddish border. They can cause noticeable pain, especially upon contact with food. Yet the appearance of a sore by itself does not reveal the cause of its formation.

Similar symptoms occur with oral infections, mucosal irritation, and other conditions. For instance, white patches can have various origins, so you should not try to diagnose the condition yourself based on a photo or a single sign.

A doctor establishes the diagnosis after an examination, and if necessary, prescribes additional tests. They take into account the nature of the changes, the treatment received, and the patient's general condition. This is especially important during chemotherapy, when the body's defenses may be weakened.

Stomatitis After Chemotherapy: What to Do at Home Every Day?

Home care helps reduce additional mucosal irritation and keeps the oral cavity clean. However, it does not replace the treatment selected by an oncologist or dentist. If painful changes appear in your mouth, it is best to inform your medical team, even if the symptoms currently seem mild.

Start with a daily oral examination. In good lighting, look at your tongue, the inside of your cheeks, your gums, and your lips. Pay attention to redness, sores, white spots, and areas that have become especially sensitive.

Choose a very soft toothbrush for brushing your teeth. Move carefully, without pressing on the gums and painful areas. If a regular brush causes pain, discuss a temporary alternative with your medical team.

Pay attention to oral hygiene after eating and before bed. Doctors may recommend special rinses, including water-based solutions with salt and baking soda. However, it is best to check the proportions and frequency with a nurse or doctor: individual recommendations depend on the state of the mucosa and the specifics of treatment.

Do not use alcohol-based mouthwashes and aggressive disinfectants for the mouth on your own. They can further irritate the inflamed mucosa. If your usual toothpaste causes a burning sensation, ask a specialist to pick a more suitable option.

When experiencing dryness, taking small sips of water regularly is helpful. You can keep a glass nearby to drink as needed. Some people find relief in ice chips, frozen desserts without irritating additives, or sugar-free chewing gum, provided chewing does not cause pain.

A neutral moisturizing balm works well for the lips. If the mucosa dries out constantly, discuss special saliva substitutes and other oral moisturizing products with your doctor.

In cases of significant pain, the medical team may suggest local anesthetics, special mouthwashes, or medications to reduce inflammation. What is used to treat stomatitis after chemotherapy depends on the cause and severity of the symptoms. There is no universal remedy that suits every patient.

What to Eat When Your Mouth Hurts and Swallowing Is Hard?

Nutrition during stomatitis must prioritize the condition of the mucosa above all else. If chewing is unpleasant, choose soft, moist dishes that are easy to swallow. You do not need to force yourself to eat foods that cause pronounced burning or pain.

Vegetable purees, soft porridges, gentle pureed soups, cottage cheese, yogurt without acidic additives, and other familiar foods of a suitable consistency work well. Dry food can be softened with sauce or a small amount of liquid. If swallowing is difficult, the consistency of your food should be discussed with a specialist.

It is best to temporarily give up foods that irritate the mucosa mechanically or chemically. These include crackers, chips, hard bread crusts, spicy seasonings, heavily salted dishes, and acidic drinks. Avoid food and drinks that are too hot.

Orange, lemon, and other acidic juices can cause a burning sensation. If even a small amount of a drink is unpleasant, replace it with water or another suitable option. When your sense of taste changes, you can try various neutral foods, guided by your tolerance.

Do not forget about getting enough fluids. Mouth pain sometimes leads a person to drink less. This is dangerous because of dehydration, especially if nausea or vomiting are present at the same time.

If your food intake has dropped noticeably due to stomatitis, let your oncologist know. If necessary, they will refer you to a clinical nutritionist who can help select a meal plan tailored to the body's needs during anti-tumor therapy.

What Do I Advise for Stomatitis After Chemotherapy?

Do not irritate the mucosa with food and drinks that are too hot. In my book, I write separately that hot tea, coffee, and soup irritate the mucous membrane of the mouth and esophagus. In my opinion, during stomatitis it is especially important not to aggravate already existing discomfort. Therefore, I advise paying attention to the temperature of your food and choosing things that do not cause pain.

Do not rush while eating. In the book "ABC of Health," I draw attention to the habit of swallowing chunks without waiting for the food to mix sufficiently with saliva. I believe that a gentle approach to eating is especially important when the oral mucosa is damaged and sensitive. Try to choose food of a suitable consistency and do not force yourself to eat what causes pain.

Do not turn eating into an extra test for the body. In my books, I advocate for plant-based foods and moderation in eating. I connect everyday dietary habits with a person's overall condition. But when experiencing mouth pain, I would primarily focus on food tolerance: soft cooked vegetables and neutral food may be more comfortable than rough, acidic, or spicy items. At the same time, I do not urge restricting your diet or going on fasting days.

Do not forget that a person is more than just a single symptom. In my books, I repeatedly emphasize the importance of general condition, nutrition, and daily routine. In my view, caring for a person must take into account their strength, rest, and emotional state, rather than being limited to a single manifestation of illness. However, medicine views stomatitis after chemotherapy primarily as a potential complication of anti-tumor treatment that requires special oral care and medical supervision.

All these thoughts should be viewed only as an addition to professional care. Before using any herb, supplement, or changing your diet, inform your oncologist. In case of severe pain, inability to drink or eat, or a fever, you must promptly contact your treating oncology team.

What Not to Do During Chemotherapy Without a Doctor's Permission?

Even natural foods and supplements can interact with anti-tumor drugs. During treatment, the body is especially sensitive to changes, so you should not start taking herbal concentrates, vitamin complexes, and other remedies on your own.

The following products and substances require special attention:

• St. John's wort. Can alter the concentration of certain anti-tumor drugs in the body and affect treatment results.
• Grapefruit and its juice. Are capable of affecting the metabolism of certain medications and changing their concentration in the blood.
• High doses of antioxidants. Taking them without coordinating with your oncologist during chemotherapy and radiation therapy is undesirable.
• Concentrated herbal extracts. They can interact with medications even if normal consumption of the corresponding plant as food causes no problems.

At the same time, regular vegetables and fruits are not under a blanket ban. They can be included in your diet keeping your tolerance and the medical team's recommendations in mind. For example, applesauce or a soft pear can be suitable options if they do not cause pain in the mouth.

Propolis, mumijo, herbal infusions, and other natural remedies sometimes used in naturopathy should not be independently applied to treat stomatitis during chemotherapy. Their use must be pre-approved by your oncologist, as the compatibility of such remedies with anti-tumor drugs requires individual evaluation.

Also, do not start cleansing procedures, fasting, strict diets, or detox programs during chemotherapy without coordinating with your oncologist. Any significant dietary changes and wellness procedures must be discussed with the medical team beforehand.

When to See a Doctor

Certain symptoms during chemotherapy require immediate attention. Do not wait for them to pass on their own or for your next scheduled appointment.

First — signs that require calling an ambulance immediately:

• Sudden or severe pain, pressure, or tightness in the chest, especially if accompanied by shortness of breath, cold sweat, or pronounced weakness. Do not write off such symptoms as heartburn or ordinary malaise.
• Severe shortness of breath, sudden lack of air.
• Fainting or a state close to losing consciousness.
• Rapid heartbeat, especially when accompanied by weakness, dizziness, or deteriorating well-being.
• Significant bleeding, blood in vomit or stool, black tarry stool.
• Sudden leg swelling, especially if accompanied by pain, redness, or a feeling of heat.

Call an ambulance immediately if you experience these signs. Do not try to cope with dangerous symptoms at home on your own and do not delay calling to wait for a consultation.

When you must contact your oncologist immediately:

• A temperature of 38 °C or higher during chemotherapy.
• Chills, shivering fits, pronounced feelings of heat or cold, even if the temperature has not been measured yet.
• Signs of a possible infection: worsening sore throat, cough, diarrhea, or painful urination.
• Pain and swelling in a leg or arm, especially if the limb has become hot and painful.
• Vomiting lasting more than a day, or the inability to drink fluids.

Contact your oncologist immediately if your temperature reaches 38 °C or higher during chemotherapy. Do not try to bring the fever down on your own before receiving medical advice: a temperature spike can be a sign of infection against the backdrop of lowered bodily defenses.

When you need to see a doctor for a routine or urgent appointment regarding your mouth:

• Painful sores, white spots, or noticeable redness have appeared.
• Pain in the mouth, lips, or throat interferes with normal eating, drinking, or sleeping.
• Mucosal dryness has increased, and unpleasant taste changes have appeared.
• Chewing or swallowing is becoming difficult.
• Changes in the mouth persist or worsen despite gentle care.

Do not delay a visit if pain has caused you to drink or eat less. Dehydration and inadequate nutrition can further complicate treatment tolerance. An oncologist or dentist will assess the condition of the mucosa, rule out other causes of the symptoms, and select suitable care and treatment products.

Read more about how I work with this topic on the "Oncology" page.

Boris Wydoff — naturopath and author, Ph.D. in nutrition. For over fifty years I have helped people restore health through nutrition, cleansing and the power of the mind — in Europe, America and Asia. About the author →

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