This page gives you information about the medical condition of dry mouth (xerostomia) and will answer some of the commonly asked questions.

What is dry mouth?

Dry mouth is a condition that affects many people. You might experience a range of problems from having a totally dry mouth to having lots of thick mucus. It affects those who have had radiotherapy treatment to the throat or mouth. It can also affect people who have had a shock or have diabetes.

Why is saliva important?

Saliva is a fluid produced in the mouth by lots of glands. There are 2 large glands in front of your ears and under your chin. These are called the parotid glands and the sub-mandibular glands. Saliva is important as it keeps your mouth and throat moist, helps with the start of food digestion and fights bacteria.

What causes a dry mouth?

Radiotherapy is used to treat some forms of head and neck cancer. While treating cancer, normal tissue receives some radiotherapy, which cannot be avoided. Some or all of the salivary glands can be affected and may lead to a reduction or total loss of saliva.

How long does it last?

This depends upon the person and what treatment they have received. There may be some recovery after a period of time but it can also be permanent.

Is it common to have thick secretions?

It is quite common for people who have had radiotherapy to have thick secretions. Salivary glands may have been damaged through radiotherapy and the saliva that is produced is very thick. This can also be considered a form of dry mouth. Thick secretions may make swallowing more difficult.

Having difficulty with jaw opening

After radiotherapy, the pain that you can suffer may cause you to hold your jaw quite stiffly. This can lead to long-term stiffness. It can also affect people who have had surgery as well as radiotherapy. The muscles involved can become stiff and stop the mouth from opening fully. Exercise can help. Your doctor, clinical nurse specialist or speech and language therapist will be able to advise you on this.

I have an unpleasant taste in my mouth

This can be due to taste changes (see ‘Altered taste’ below), but may also be caused by fungal infections or bacterial infections. It is important to keep your mouth as clean as possible.

Good oral hygiene is important and regular trips to the dentist, if you have your own teeth, are essential. Try using plastic cutlery if you notice a metallic taste in your mouth.

Altered taste

Again, taste changes may happen after radiotherapy and can recover after a period of time or may be permanent. There are usually specific food types that are affected and can vary from person to person. Try avoiding that food type for a while and try it again at a later date.

Top tips for coping with a dry mouth

  • Take regular sips of water.
  • Drink at least 2 litres (or 8 glasses) of water in 24 hours.
  • Always drink water with your meal, especially before you take a mouth full of food. This will help with lubricating your swallow.
  • Remember to keep water by your bed for drinking during the night.
  • Try bottles with a non-return valve that does not spill. Small ones can be purchased from supermarkets and fit into your pocket for use at any time.
  • Try a small spray bottle with water in it.
  • A little lemon juice added to the water is refreshing but this may be an irritant if your mouth is still sore from treatment.

Some people find pineapple helpful as it stimulates saliva production, again this may be too sharp immediately the following radiotherapy. This depends on each person’s level of dry mouth.

  • Try cucumber that has been kept in the fridge.
  • Olive oil rubbed around the inside of your mouth the last thing at night will help to reduce the dryness felt in your mouth first thing in the morning.
  • Clean your teeth and tongue regularly, after meals as well as morning and night. You may find sensitive toothpaste or one free of foaming agent is better.
  • If you wear dentures, remove them at night and always keep them clean.
  • Visit your dentist every 6 months, if you have your own teeth.
  • If you use mouthwash, you may find an alcohol-free type more comfortable.
  • Evidence shows that salt-water mouthwashes are just as effective as commercially bought mouthwashes.
  • Keep your lips moist with petroleum jelly (not during radiotherapy treatment). Moisturising cream is a good alternative to petroleum jelly.
  • Try artificial saliva products. What may work for one person may not work for another. Do not give up! Your clinical nurse specialist will advise you if any new products become available.
  • Chewing gum can help stimulate more saliva.
  • Always maintain a healthy and well balanced diet. If you feel you are not eating enough, let your doctor, one of the nurses or your dietician know.
  • Avoid sugary drinks and food, or clean your teeth afterward.


If you have any other questions you wish to ask, please do not hesitate to contact the:

Clinical Nurse Specialists

Tel: 0300 422 6785

Monday to Friday, 8:00am to 4:00pm

Printable version of this page

Dry mouth Department: Ear, Nose and Throat Review due: August 2025 PDF, 159.3 KB, 4 pages
Reference number GHPI0591_08_22
Department Ear, Nose and Throat
Review due August 2025