Dry Mouth (Xerostomia)
Dry mouth, also known as xerostomia, may be caused by radiation therapy given to the head and neck area or by medications used to treat cancer or side effects. Patients receiving radiation to the head and neck may experience a change in the production and quality of saliva. During treatment for cancer, saliva production actually increases, due to irritation caused by the radiation or chemotherapy (if given). During treatment, the saliva tends to be thicker, often described by patients as "ropey" and difficult to control. After treatment, the excessive saliva goes away and the mouth becomes dry. This can be a temporary side effect, getting better completely or partially over the year after treatment, or leading to a permanent loss of saliva production.
Dry mouth may affect speech, taste sensation, ability to swallow, and the use of dentures. Patients may report a sore or burning sensation, cracked lips, and fissures (splits) in the corners of the lips. Normal saliva has enzymes that protect the teeth and gums from bacteria, keeping them healthy. In turn, there is an increased risk of developing cavities, periodontal disease and ultimately, tooth loss due to less saliva.
Can dry mouth be prevented?
The extent of dry mouth depends on the radiation technique used, the dose of radiation received by the salivary glands, and how much of the salivary gland has received radiation. Advanced radiation techniques are aimed at preventing or reducing the extent and permanence of xerostomia. With these techniques, the salivary gland on the side opposite of the cancer receives a lower dose of radiation; therefore, loss of salivary function may be less and may get better sooner following the completion of treatment.
What can I do if I have dry mouth?
If you have xerostomia, there are things you can do to help deal with your dry mouth and prevent cavities and periodontal disease. Try to follow these simple guidelines:
- Perform oral hygiene at least four times per day (after each meal and before bedtime).
- Floss once a day.
- The mouth (oral cavity) should be rinsed immediately after meals.
- Dentures need to be brushed and rinsed after meals.
- Only use toothpaste with fluoride when brushing.
- Keep water handy to keep the mouth moist at all times. Sip water or spray it in the mouth regularly.
- Apply prescription strength fluoride gel at bedtime unless you do not have any teeth.
- Rinse with salt and baking soda solution 4-6 times a day (1 tsp. salt, 1 tsp. baking soda, and 1 quart of water).
- Chew sugar free gum/suck on sugar free hard candy or drink diet ginger ale to stimulate saliva production.
- Avoid liquids and foods with high sugar content.
- Limit coffee, tea, and alcohol as these will make dry mouth worse.
- Avoid dry foods, such as bread, dry meat, toast, crackers, and snack foods that are dry and salty.
- Add sauces or gravies to food to make them more moist.
- Avoid rinses that have alcohol.
- Avoid antihistamines which can dry the area more.
- Use moisturizer regularly on the lips.
- Salivary substitutes or artificial saliva preparations may relieve discomfort by temporarily wetting the mouth and replacing some of the constituents of saliva.
- Oral pilocarpine (Salagen) is a medication approved by the FDA to stimulate saliva secretion from the remaining salivary glands. It is not appropriate for everyone with dry mouth, and it can only be obtained with a prescription from your provider.
- Biotene® products (mouthwash, toothpaste and chewing gum that have the pH of saliva) are available without a prescription and can be effective for treating dry mouth.
- Use a cool mist humidifier at night in the bedroom to provide humidity, especially in winter months when the house is heated.
- See your dentist every 3 months for cleaning and a dental health checkup.
- Acupuncture may increase saliva production for people who still produce some saliva naturally.
Dry mouth can be a challenging side effect to deal with on a daily basis. Contact your care provider for help with managing this side effect.
American Head & Neck Society. Xerostomia. https://www.ahns.info/survivorship_intro/xerostomia-2/
Head and Neck Cancer Alliance. 2017. Dry Mouth. https://www.headandneck.org/dry-mouth/