Why Is My Mouth Dry All the Time?

what does a dry mouth mean?Does your mouth constantly feel dry and sticky, even if you drink plenty of water? You might have a condition known as dry mouth syndrome (also called xerostomia).

As well as feeling uncomfortable, a persistently dry mouth can also increase your risk of developing other oral health problems such as tooth decay and gum disease, so it's important to see a dentist and discuss treatments.

Dry mouth syndrome can have many possible causes, from side-effects of medication and medical treatments to breathing disorders and other health conditions. Lifestyle factors such as smoking and drinking alcohol can also contribute to mouth dryness.

Read this short guide to find out what might be causing your dry mouth, why it matters and what treatments may be effective for you.

Do I have dry mouth syndrome?

It's thought that around 10 percent of Australians have dry mouth syndrome, which is even more common with age. This happens when the salivary glands in the back of the mouth stop functioning normally and less saliva is produced.

As well as a feeling of dryness in the mouth, tongue and throat, other common symptoms of dry mouth syndrome can include:

  • rough or sticky tongue surface
  • thicker or stringy saliva
  • burning sensation in the mouth
  • persistent cough or sore throat
  • trouble swallowing
  • reduced sense of taste
  • bad breath
  • dry or cracked lips
  • mouth ulcers
  • dentures coming loose
  • infections such as oral thrush
  • signs of tooth decay or gum disease

Tooth decay from a dry mouth usually looks different to standard decay. Rather than starting at the crown of the tooth, the decay tends to be found next to the gum line. This can irritate the gums, leading to gingivitis (gum disease), or cause the gums to recede.

Symptoms of dry mouth syndrome may also be present outside the mouth, such as:

  • dry or itchy eyes or nose
  • reduced sense of smell
  • joint pains
  • weight loss
  • constipation
  • thrush infections

These symptoms may point to dry mouth syndrome or another condition, so it's important to see an experienced dentist to get a thorough diagnosis.

Why is saliva important?

Saliva has many important roles for protecting your oral health and general health.

As a natural cleanser and disinfectant for the mouth, saliva helps to wash away leftover food from the surfaces of your teeth. It also has properties that kill bacteria and helps to neutralise acids released by bacteria in plaque that can cause tooth decay and erosion.

If your saliva glands aren't functioning normally, less saliva will be produced and you'll be at higher risk of tooth decay and other oral health problems. If a tooth has already been damaged, saliva also contains calcium and phosphorus that can help to rebuild tooth enamel.

Saliva also plays an important role in eating and getting the nutrition your body needs. Without lubrication from saliva, chewing and swallowing can be more difficult and digestion may also be affected. Saliva also helps you to taste flavours and textures for more satisfying experiences with food.

What causes a dry mouth?

Dry mouth may be temporary or long term, and it may be caused or aggravated by a number of things. While there are ways to manage a dry mouth and stimulate saliva flow, your dentist will aim to understand what's casing your mouth dryness so they can treat the problem at the source.

Common causes of dry mouth include:


The most common reason for a dry mouth is not drinking enough fluids, especially water. Dehydration can also affect body functions, so it's important to drink the recommended 8 glasses of water per day to stay hydrated, or more if you're exerting yourself or the weather is hot and dry. The risk of dehydration will be higher if you have a medical condition such as blood loss or kidney failure.

Not all drinks help equally with a dry mouth. Alcoholic drinks, coffee, tea and soft drinks are less hydrating as diuretics remove water from the body. While sports drinks can help to replenish fluids rapidly, their often high sugar content makes them unsuitable for regular drinking, as this increase tooth decay risk.

Plain water is the best source of hydration for your mouth and body, especially if your local tap water supply contains fluoride, which helps to protect teeth against decay.


Medications are a surprisingly common cause of dry mouth. Many prescription and over-the-counter medicines list dry mouth as a possible side effect, including some:

  • analgesics
  • antidepressants
  • antihistamines
  • decongestants
  • sedatives
  • medications for high blood pressure

If you think that a medication you're taking might be responsible for your dry mouth, and this could continue to be a problem, talk to your doctor to find out if there's an alternative you can switch to. Don't change medications without first consulting a professional.


Drinking alcohol, smoking or chewing tobacco and illegal drugs also reduce saliva production, which can lead to temporary or long-term dry mouth. These activities also increase your risk factor for other oral health problems, including tooth decay, gum disease and oral cancer, along with general health risks.

Health conditions

Certain illnesses and other health conditions can cause inflammation around the salivary glands, affecting their function and causing dry mouth. These include:

  • autoimmune diseases such as AIDS, primary biliary cirrhosis, rheumatoid arthritis, scleroderma, Sjögren's syndrome and systemic lupus erythematous
  • infections such as hepatitis C, mumps and sinusitis
  • psychiatric illnesses such as anorexia nervosa and bulimia, anxiety and stress
  • neurological disorders such as Alzheimer's disease, Parkinson's disease and cerebral palsy
  • other health conditions including amyloidosis, diabetes, stroke and oral thrush

Some medical treatments such as chemotherapy and radiotherapy of the head and neck can also impair the function of the salivary glands, either temporarily or permanently.

Mouth breathing

Adults and children who breathe through their mouth rather than their nose are more likely to have a dry mouth. This usually happens when the nasal passages are blocked by congestion, a deviated septum, large adenoids or tonsils or irregular development of the nose or jaw.

Mouth breathing can sometimes be corrected through breathing retraining, but other times it may involve surgery.

Snoring and sleep apnoea

Snoring and sleep disorders may be related to other breathing disorders or caused by an excess of tissue in the throat. If you frequently stop breathing and wake up in the night, you may have obstructive sleep apnoea (OSA), which carries its own health risks.

Other obstructions

Saliva flow can be restricted if the salivary ducts themselves are obstructed. This can happen if minerals contained in saliva accumulate. Damage to nerves in the face, head or neck by an impact or surgery can also sometimes affect the function of the salivary glands.

How can a dentist help with dry mouth?

If you're concerned about dry mouth symptoms, a dentist is the best qualified professional to talk to.

During your appointment at the dental clinic, your dentist will examine your teeth and mouth for signs of dry mouth syndrome and related problems such as tooth decay that may also need treatment. This may require an x-ray or other imaging to help with diagnosis and treatment planning.

Your dentist will also ask about your medical history, any medications you're taking, lifestyle factors and other information to help them determine the likely cause of your dry mouth. If it's not clear what's affecting your salivary glands, they may arrange a blood test or refer you to another professional who can run more tests.

Dry mouth treatments

Your dentist may be able to provide products to relieve a dry mouth, such as an artificial saliva substitute, lubricating mouthwash or other moisturisers. However, these only address the symptoms, not the cause.

For long-term relief from dry mouth, your dentist or other professional may recommend:

  • treating or managing an underlying infection or medical condition
  • changing your medication to one that doesn't cause dry mouth as a side effect
  • surgery to remove obstructions
  • treatment for associated problems such as mouth breathing or sleep apnoea

If dry mouth has contributed to other oral health problems, such as tooth decay or gum disease, your dentist will recommend treating these at the same time.

How to manage a dry mouth at home

It's not always possible to reverse dry mouth syndrome. If your saliva flow will continue to be restricted, you can try to reduce discomfort and lower your risk of developing other oral health problems by:

  • Drinking plenty of water throughout the day and rinsing your mouth while eating
  • Avoiding or cutting down on alcohol, caffeine, tobacco and other substances
  • Eating chewy foods or chewing gum to stimulate the saliva glands
  • Avoiding very dry or crunchy foods and sugary or acidic drinks
  • Spending longer chewing food before you swallow
  • Breathing through your nose rather than your mouth
  • Using a humidifier if the air in your bedroom is dry
  • Looking after your oral hygiene with twice daily tooth brushing, daily flossing and regular dental check-ups

Talk to a dentist in Sydney CBD

If you have a dry mouth and you want to know more about your treatment options, schedule an appointment with our experienced dentists at Sydney CBD Dental. Call our George Street dental clinic on (02) 9232 3900 or book online.


Better Health Channel. Dry mouth syndrome [Online] 2017 [Accessed August 2020] Available from: https://www.betterhealth.vic.gov.au/health/ConditionsAndTreatments/dry-mouth-syndrome

Healthdirect. Dry mouth syndrome [Online] 2018 [Accessed August 2020] Available from: https://www.healthdirect.gov.au/dry-mouth-syndrome