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Dry Mouth: Causes, Effects on Your Teeth and What Helps

A dry mouth is common and usually not serious in itself, but saliva protects your teeth. Here is what causes it, what helps, and when to get it checked.

Updated September 2026·By the OHA editorial team·6 min read·How we write
Key takeaways
  • A dry mouth (medical name xerostomia) means your mouth is not making enough saliva to stay moist.
  • Common causes include not drinking enough, side effects of medicines, breathing through your mouth at night, anxiety, cancer treatment, and conditions such as diabetes and Sjögren's syndrome.
  • Saliva protects your teeth, so a mouth that stays dry raises the risk of tooth decay, gum disease and mouth infections.
  • Sipping water, chewing sugar-free gum, cutting down on alcohol and caffeine and not smoking can all help, along with extra care for your teeth.
  • Never stop a prescribed medicine on your own. If you think it is drying your mouth, talk to your doctor.

The US National Institute of Dental and Craniofacial Research (NIDCR) says a dry mouth can happen to anyone occasionally, for example when nervous or stressed. healthdirect Australia and the Australian Dental Association both report that about 1 in 3 adults say they have had a dry mouth at some point. The NHS says a dry mouth is rarely a sign of anything serious. But when it keeps happening, it can make chewing, swallowing and talking difficult, and it matters for your teeth, because saliva is one of their natural defences.

Why does saliva matter?

NIDCR explains that saliva moistens and breaks down food, helps you swallow, washes food away from your teeth and gums, and contains minerals such as calcium and phosphate that help keep teeth strong and fight decay. It also helps keep harmful germs in check. The American Dental Association adds that saliva neutralises the acids made by bacteria in the mouth, and calls it the mouth's primary defence against tooth decay.

What are the symptoms of a dry mouth?

Along with the dry feeling itself, NIDCR and healthdirect list symptoms such as:

  • a sticky feeling in the mouth, or a dry throat
  • trouble chewing, swallowing, tasting or speaking
  • a burning feeling in the mouth
  • a rough, dry tongue that may stick to the roof of your mouth
  • dry, cracked lips, and saliva that feels thick or stringy
  • mouth ulcers or sores, and infections such as oral thrush
  • bad breath

What causes a dry mouth?

There is often more than one possible cause, and the Australian Dental Association notes that sometimes the cause is not known.

  • Not drinking enough. The NHS lists dehydration as one of the main causes, for example from not drinking enough, sweating a lot or being ill.
  • Medicines. NIDCR says hundreds of medicines can make the salivary glands produce less saliva, including medicines for high blood pressure, depression and bladder control. healthdirect also lists antihistamines, decongestants and painkillers including opioids. The NHS suggests checking your medicine's leaflet to see whether dry mouth is a listed side effect.
  • Breathing through your mouth. The NHS says this can dry your mouth at night, for example if you have a blocked nose or sleep with your mouth open. healthdirect lists snoring as a risk factor.
  • Health conditions. The NHS says a dry mouth that does not go away may be caused by a condition such as diabetes or Sjögren's syndrome. The American Dental Association describes Sjögren's as a long-term autoimmune condition, in which the immune system attacks the body's own moisture-producing glands, including those that make tears and saliva. healthdirect lists other linked conditions, including stroke, Alzheimer's disease, lupus, rheumatoid arthritis and nerve damage to the head or neck.
  • Cancer treatment. Radiotherapy can damage the salivary glands, and NIDCR says some cancer drugs make saliva thicker.
  • Lifestyle. The NHS lists anxiety. The Australian Dental Association and healthdirect also list smoking and drinking a lot of alcohol, tea, coffee or soft drinks, and healthdirect includes recreational drugs such as methamphetamine and marijuana.
Is a dry mouth just part of getting older?

The sources put this differently. healthdirect lists older age as a risk factor for dry mouth. NIDCR says dry mouth is not a normal part of ageing, and that if you think you have it, you should see your dentist or doctor to find out why. Whatever your age, a dry mouth that does not go away is worth getting checked.

Why is a dry mouth a problem for your teeth?

Without enough saliva, your teeth lose much of their natural protection. healthdirect says dry mouth greatly increases your chance of tooth decay or gum disease, and the Australian Dental Association says decay can develop faster in a dry mouth. NIDCR adds that dry mouth raises the risk of fungal infections in the mouth.

What can help?

Things you can do yourself

The NHS, NIDCR, healthdirect and the Australian Dental Association give similar advice:

  • Drink plenty of water. The NHS suggests regular sips through the day and keeping water by your bed. NIDCR suggests 8 to 12 cups a day (about 2–3 litres). If a doctor has told you to limit fluids, for example because of kidney disease, keep to their limit instead: see kidney disease and oral health.
  • Sip water with meals, and choose moist foods such as soups, or add sauces, to make chewing and swallowing easier.
  • Chew sugar-free gum or suck sugar-free sweets to get saliva flowing. The NHS says sucking ice cubes can also help.
  • Cut down on alcohol, caffeine and fizzy drinks, and do not smoke.
  • Avoid foods that can irritate a dry mouth, such as acidic, spicy or salty foods, and, healthdirect adds, foods with sharp edges like crackers or chips.
  • Use a humidifier at night, and try to breathe through your nose rather than your mouth, as healthdirect suggests.
  • Take dentures out at night and keep them clean.

Some sugar-free gums and sweets contain xylitol, a sweetener. NIDCR says it may help prevent cavities, and the Australian Dental Association says it can help prevent tooth decay. The Australian Dental Association also cautions that chewing gum might not be a good idea if you have jaw pain or a jaw problem.

Protecting your teeth

  • Brush twice a day with a fluoride toothpaste and a soft toothbrush, and clean between your teeth every day.
  • The NHS suggests an alcohol-free mouthwash. healthdirect suggests a toothpaste and mouthwash with higher levels of fluoride, and avoiding toothpastes that cause a burning feeling.
  • Avoid sticky, sugary and acidic foods and drinks.
  • Have regular dental check-ups. The Australian Dental Association says people with a dry mouth may need to visit more often, so decay is found early.

In Australia, the Australian Dental Association notes that high-fluoride toothpaste is sold in pharmacies and some dental clinics, not supermarkets. Ask your dentist whether it is right for you.

Help from a pharmacist, doctor or dentist

The NHS says a pharmacist can advise on gels, sprays, tablets or lozenges that help keep the mouth moist, as not all products suit everyone. It also advises against acidic artificial saliva products if you have your own teeth.

To find the cause, NIDCR says your doctor or dentist will review your medical history and medicines, and may suggest blood tests or a test of how much saliva you make. healthdirect says the best way to treat dry mouth is to treat the cause. Options the sources describe include changing a medicine or its dose, medicines that help the salivary glands make more saliva, and artificial saliva.

The NHS, healthdirect and the Australian Dental Association all stress the same thing: do not stop or change a prescribed medicine yourself, even if you think it is causing your dry mouth. Talk to your doctor first.

When to see a dentist

See a doctor (GP) or dentist if you have a dry mouth and:

  • it makes talking or eating difficult, or you are struggling to eat regularly
  • it has not improved after a few weeks of trying home or pharmacy treatments
  • you have problems with your sense of taste that are not going away
  • your mouth is painful, red, swollen or bleeding, or you have sore white patches in your mouth
  • you think a prescribed medicine might be causing it
  • you have other symptoms, such as needing to pee a lot or dry eyes
  • you notice signs of tooth decay, such as toothache or a sharp pain with hot, cold or sweet things

Frequently asked questions

Is a dry mouth a sign of something serious?

Usually not. The NHS says a dry mouth is rarely a sign of anything serious. But one that does not go away can be caused by a condition such as diabetes or Sjögren's syndrome, so see a GP if it persists or you have other symptoms, such as dry eyes or needing to pee a lot.

Can my medicine cause a dry mouth?

Yes. NIDCR says hundreds of medicines can reduce saliva. Do not stop a prescribed medicine on your own. Your doctor may be able to change the medicine or the dose, or suggest other treatments.

Why is my mouth drier at night?

Breathing through your mouth while you sleep, for example because of a blocked nose, is one reason the NHS gives. The Australian Dental Association notes that dry mouth is often more noticeable at night. Keeping water by your bed and using a humidifier may help.

Sources

  1. Dry mouth, NHS, accessed September 2026
  2. Tooth decay, NHS, accessed September 2026
  3. Dry mouth syndrome, healthdirect Australia, accessed September 2026
  4. Dry mouth, Australian Dental Association, accessed September 2026
  5. Dry mouth, National Institute of Dental and Craniofacial Research (NIH), accessed September 2026
  6. Dry mouth, American Dental Association (MouthHealthy), accessed September 2026

This article is general information about oral health. It is not a diagnosis or a substitute for advice from a dentist or doctor who knows your situation. If you have pain, swelling, bleeding that does not settle, or a problem that is getting worse, see a dental professional. In an emergency, contact your local emergency service.

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