Dry mouth

Also known as xerostomia (sounds like ZEER-oh-STOH-mee-ah) or salivary hypofunction

Dry mouth is a condition where there is not enough saliva in your mouth.

Key points about dry mouth

  1. Dry mouth can be caused by dehydration, medicines, medical conditions and cancer treatment.
  2. Symptoms include a feeling of sticky dryness in your mouth, needing to sip water a lot, bad breath and mouth sores.
  3. Dry mouth can usually be treated with self-care or pharmacy treatments.
  4. If these don't fix your dry mouth in a few weeks, see your doctor as there may be an underlying cause.
  5. Dry mouth can contribute to tooth decay, gum disease and mouth infections, so you need to take extra care of your oral health.
See your GP or doctor if you experience any of the following:
  • your mouth is still dry after a few weeks of self-care and pharmacy treatment
  • you have difficulty chewing, swallowing or talking
  • your mouth is painful, red or swollen
  • you have sore white patches in your mouth
  • you think your dry mouth is caused by your medicines
  • you have symptoms other than dry mouth, eg, dry eyes or needing to go to the toilet more often.

What does saliva do? 

Saliva is produced by several types of salivary gland, which release saliva at different places in your mouth. Each type of gland makes a slightly different form of saliva.

Saliva has several roles. These include:

  • cleaning your mouth by breaking down food particles and washing them towards your throat
  • lubricating your mouth (keeping it moist), which stops chafing and rubbing
  • keeping acid at the right level in your mouth
  • repairing your teeth with proteins that bind calcium and phosphate and coat your teeth with them
  • keeping bugs away by fighting bacteria, viruses and fungi
  • using its enzymes to break food down into a form that means you can taste and digest it
  • protecting and allowing replacement of the membrane that lines your mouth, throat and nose.

What causes dry mouth?

Common causes include:

What are the symptoms of dry mouth? 

Common symptoms of dry mouth include:

  • feeling a sticky dryness in your mouth
  • needing frequent sips of water, particularly when speaking
  • difficulty speaking, eating and swallowing
  • thick or stringy saliva
  • a dry or sore tongue
  • bad breath (halitosis)
  • sores in and around your mouth
  • changes in your taste 
  • a burning sensation in your mouth.

What are the complications of dry mouth?

Ongoing dry mouth can lead to complications such as:

Dry mouth – causes, symptoms, treatments and more

(Rehealthify, 2015)

How is dry mouth diagnosed? 

Your doctor will ask you questions about your symptoms and also about any other conditions or factors that could be causing your dry mouth. They may also check your mouth and see if you have any complications such as sores, tooth decay or oral thrush.

Usually no tests are needed, unless your doctor wants to rule out other conditions. 

How is dry mouth treated? 

Dry mouth can usually be treated at home with self-care measures or over-the-counter medicines from your pharmacy. Ask your pharmacist about treatments.

These may include:

  • gels
  • sprays
  • tablets or lozenges. 

If your mouth is still dry after a few weeks of trying self-care or pharmacy treatment, see your doctor as there may be an underlying cause. 

Treatment aims to remove the underlying cause of your dry mouth, eg, if your doctor thinks your medicine is causing your dry mouth, they will review your medicines and may reduce the dose.

If your dry mouth is caused by a medical condition, the treatment will focus on that. Your doctor may also prescribe medicine to stimulate production of your saliva. 

How can I care for myself with dry mouth?

Care for dry mouth

There are  a number of self-help measures you can try.

  • Take frequent sips of water or suck ice cubes to moisten your mouth.
  • Keep water by your bed at night.
  • Suck sugar-free sweets or chew sugar-free gum to stimulate saliva production. Limit their use, as too much of the sugar substitute can cause diarrhoea (runny poos).
  • Avoid alcohol, caffeine and smoking, as these make a dry mouth worse.
  • Try over-the-counter saliva substitutes or oral moisturisers.
  • Apply lip balm or lip moisturiser to your lips to prevent drying and cracking. 
  • If you smoke, get support to quit.

If you think your medicine is causing your dry mouth, don't stop it without getting advice from your doctor. 

Care of your teeth and gums 

Gum inflammation and cavities are a greater problem for people with dry mouth, so good daily oral care is particularly important. Also see your dentist and dental hygienist regularly.

Learn more

What is dry mouth? Cancer Society, NZ
Dry mouth NHS, UK 


  1. Dry mouth HealthInfo Canterbury, NZ
  2. Dry mouth (xerostomia) Patient Info, UK

Reviewed by

Dr Arna Letica has worked as a GP for over 13 years, with particular interests in women's and children's health. She is currently focusing on non-clinical roles, including working as a medical assessor.
Credits: Health Navigator Editorial Team. Reviewed By: Dr Arna Letica, FRNZCGP, Auckland Last reviewed: 28 Sep 2021