Review date: October 2022

This information is taken from a leaflet by The British and Irish Society for Oral Medicine.

Aims

This information has been written to help you understand the complaint of dry mouth.

It provides general information on dry mouth, including its causes, how it is investigated and any potential complications. Additional sources of information have been included if you wish to find out more about dry mouth.

What is dry mouth?

The complaint of dry mouth, also known as xerostomia, is generally due to a decreased amount of saliva.

Some people do however complain of dry mouth despite having adequate saliva in their mouth.

Dry mouth can be a short term or long-term complaint depending on its cause. It may be better or worse at a particular time of the day e.g. night-time.

What causes dry mouth?

There are a number of causes of dry mouth. These include local factors, lifestyle factors and medical conditions. Dry mouth is a common side effect of some medications.

• Mouth breathing can cause dry mouth.
• Tobacco, alcohol or recreational drug use can cause dry mouth.
• Dehydration may also worsen the complaint of dry mouth.
• Sjögren’s Syndrome (an autoimmune condition that can affect the salivary glands, tear glands and sometimes the joints), depression, anxiety and diabetes can cause dry mouth.
• Dry mouth is also a recognised side effect of some types of head and neck radiotherapy.
• Medicines such as tricyclic antidepressants, antihistamines used for allergy relief, antispasmodics used for gut problems and some antipsychotics commonly cause a dry mouth.

Is dry mouth hereditary?

Dry mouth is not thought to be hereditary.

What are the symptoms of dry mouth?

Dry mouth is a symptom, not an illness or disease.

Saliva is made by the salivary glands. It helps break down and lubricate food whilst eating. Saliva contains many minerals which help protect your teeth from dental decay.

A lack of saliva can cause:

• Difficulty with chewing and swallowing some foods
• Problems with talking
• Altered taste
• Dental decay and gum inflammation (gingivitis)
• Recurrent thrush infections (oral candida) affecting the mouth and the corners of the lips.

What does dry mouth look like?

If there is a reduced flow of saliva, the mouth may look dry, like parchment. The saliva may be frothy in appearance.

How is dry mouth confirmed?

If there is a reduced amount of saliva, a dentist or doctor may diagnose dry mouth by simple examination.

A salivary flow test, known as sialometry, can also confirm that you have dry mouth and this takes a few minutes to complete.

Other investigations including blood tests may be indicated to exclude underlying medical conditions.

What treatment is available for dry mouth?

The management of your dry mouth depends on its cause. If it is related to medication, your doctor may be able to reduce the dose or change this.

If you have little or no saliva, then a ‘saliva substitute’ can be helpful for your dry mouth. Salivary substitutes in the form of sprays, liquids and gels are available from a pharmacist but can be prescribed.

If you have some saliva, it may be possible to stimulate saliva flow. To stimulate saliva:

• Use sugar-free chewing gum.
• Sugar free pastilles are available directly from a pharmacist to help stimulate saliva flow, but these can also be prescribed.
• A medication called Pilocarpine has been shown to be useful in stimulating saliva production. It is not suitable for everyone as it has some side effects. It cannot be used if you have certain medical conditions.

Antifungal (anti-thrush) treatments in the form of liquids, gels or tablets may be prescribed if recurrent fungal infections occur. Your dentist may recommend using high fluoride toothpaste to reduce the risk of dental decay.

What can I do?

• Keep your mouth moist with regular sips of water or salivary substitutes. Keep water to hand.
• Choose wet foods or drink water while eating.
• Eat a diet low in sugar, avoid acidic fizzy drinks.
• Use high concentration fluoride toothpaste as prescribed by your dentist.
• Rinse your mouth out with water or an alcohol free, fluoride mouth wash after meals.
• Maintain good oral hygiene and visit a hygienist regularly to prevent gum disease.
• Visit your dentist regularly even if you are seen in a specialist centre.
• If you wear dentures, leave these out at night. Clean your denture with a brush to dislodge any debris. You should also soak it in a suitable denture cleaner.

Further information

Go to this page on the Mayo Clinic website for more information on dry mouth.

For more information on Sjögren's Syndrome go to this page on the British and Irish Society for Oral Medicine website.