Dry Mouth

Having a dry mouth (xerostomia) is extremely unpleasant as it affects comfort, taste and speech. It also puts the teeth at greater risk of caries and gum disease, increases the risk of getting infections in the mouth and makes dentures more difficult to tolerate.

There are many causes of a dry mouth which include the following –

• Drugs
• Sjogren's syndrome
• Radiotherapy to the head and neck region
• Sarcoidosis
• HIV

Sometimes patients may feel dryness in the mouth even though the salivary glands are working normally. This is known as subjective xerostomia.

When a patient has a dry mouth the history is important to help to exclude the causes listed above. Useful investigations include swabs, saliva samples and often blood tests. An ultrasound of the salivary glands may be helpful. When Sjogren's syndrome is being considered a biopsy of minor salivary glands from the lower lip may be suggested.

Treatment of dry mouth depends on the cause but may involve liaising with the patient's general practitioner about any drugs which are suspected of contributing to the symptoms. Chewing sugar-free chewing gum may help to stimulate saliva flow. Saliva substitutes may be prescribed in the form of sprays, gels, mouthwashes and pastilles. Occasionally drugs may be prescribed to increase saliva flow.

Patients with dry mouth need to be monitored for fungal infection in the mouth. It is also important for the patient's general dental practitioner to monitor for dental caries or gum disease.

Patients with Sjogren's syndrome need to also be monitored for any persistent lumps which develop in the salivary glands which may suggest the development of a lymphoma.