Can Immunotherapy Cause Dry Mouth and How to Manage It

Yes, immunotherapy can be linked to mouth and throat side effects, including dry mouth (xerostomia), though it tends to be less common than with some chemotherapies or head and neck radiation. ^[1] Immune-related inflammation can affect salivary glands and oral tissues, which may lead to mouth soreness, difficulty swallowing, altered taste, and feeling unusually thirsty or sticky in the mouth. ^[2] More broadly, dry mouth is a recognized problem during cancer treatment and can occur from multiple therapies, so it’s important to monitor symptoms early. ^[3]

Why Dry Mouth Happens with Cancer Treatments

• Immune checkpoint inhibitors can trigger immune reactions in various tissues; when oral tissues or salivary glands are involved, moisture and saliva flow can drop, causing dryness and discomfort. ^[1]
• Across cancer care, dry mouth may also stem from medicines, dehydration, mouth sores, or reduced saliva production, all of which can worsen eating and swallowing. ^[3]

How to Recognize It

Common signs include a sticky or parched feeling, thick saliva, trouble chewing or swallowing dry foods, increased thirst, altered taste, bad breath, or mouth sores. ^[3] If you notice you can’t keep up with fluids or pain when swallowing, you should alert your care team promptly. ^[1]

At‑Home Relief Strategies

• Rinse regularly: Swish a non‑alcohol, non‑peroxide mouthwash or plain salt/baking‑soda solution every 4–6 hours to soothe tissue and reduce irritation. ^[2]
• Choose the right rinse: Alcohol‑free, sugar‑free rinses (for example, specialized dry‑mouth rinses) are gentler on the mouth and can reduce worsening of sores. ^[2]
• Stay hydrated: Sip water frequently through the day to maintain moisture and help with swallowing. ^[3]
• Stimulate saliva: Sugar‑free lozenges or gum can encourage saliva production and ease dryness. ^[4]
• Gentle oral care: Use a soft‑bristled toothbrush, avoid very hot, acidic, salty, or spicy foods during flares, and keep lips moisturized to protect the mouth lining. ^[5]
• Avoid irritants: Skip alcohol‑based mouthwashes and tobacco products, which can worsen dryness and sores. ^[5]

When to Call Your Care Team

Contact your team if you develop frequent mouth sores, pain with eating or swallowing, or if you can’t drink enough to stay hydrated; these can signal complications that need medical treatment or adjustments. ^[5] If symptoms are severe or persistent, your team may tailor therapies, check for other causes, or prescribe targeted treatments. ^[6]

Medical Treatments Your Clinician May Consider

• Review medicines: If a medication is contributing to dryness, your clinician may adjust the dose or switch to alternatives when appropriate. ^[6]
• Moisturizing products: Options include prescription or over‑the‑counter mouth moisturizers and artificial saliva to improve comfort, especially between meals and at night. ^{[6] [7]}
• Saliva‑boosting therapies: In certain cases of significant dryness (for example, after specific treatments), prescription agents to stimulate salivary glands may be considered. ^[7]

Practical Eating and Drinking Tips

• Choose moist, soft foods (soups, stews, yogurt) and add sauces or gravies to dry foods to ease swallowing. ^[3]
• Take small sips of water during meals and keep a water bottle nearby throughout the day. ^[3]
• Limit caffeine and alcohol, which can dehydrate and worsen dry mouth. ^[8]

Simple Preventive Mouth Care Routine

• Rinse every 4–6 hours with alcohol‑free options or a salt/baking‑soda solution to keep oral tissues comfortable. ^[2]
• Keep lips and corners of the mouth protected with balm to prevent cracking and pain. ^[5]
• Maintain gentle brushing and flossing to reduce infection risk when the mouth is dry or sore. ^[5]

Key Takeaways

• Immunotherapy can be associated with oral side effects, and dry mouth may occur due to inflammation of oral tissues and salivary glands. Early attention helps prevent complications. ^[1]
• Consistent, gentle mouth care and hydration, saliva stimulation, and avoiding irritants are first‑line steps. ^{[2] [5]}
• If symptoms interfere with eating, swallowing, or hydration, seek evaluation; clinicians can adjust medicines and recommend specialized moisturizers or saliva‑stimulating treatments. ^{[5] [6] [7]}