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Understanding Dry Mouth Causes, Symptoms and Prevention

Understanding Dry Mouth Causes, Symptoms and Prevention

Most of us know what it’s like to have a dry mouth every now and then. But if your mouth feels dry most of the time you may have what medical professionals refer to as xerostomia.

This is usually when your mouth feels dry because you have a reduced flow of saliva or no saliva at all. And while it’s not an illness itself, it may be a sign or symptom of a medical condition or a side effect of a medication you may be taking.

Dry mouth is quite common, affecting at least one in 10 adults and up to 25 per cent of adults aged 65 or older (as many as 50 per cent of elderly people living in care homes may be affected) (i). The reason it’s more common in older people could be that they’re more likely than younger people to take one or more prescription medicines that can cause a problem with dry mouth.

The most obvious symptom is a feeling of dryness in the mouth. However, there are other symptoms associated with dry mouth, including:

  • Bad breath

  • Dry, cracked lips

  • Cracks and soreness in the corners of the mouth

  • Distorted sense of taste (dysgeusia)

  • Oral fungal infections such as oral thrush

  • Painful tongue, including tongue ulcers

  • Sticky or stringy saliva

  • Burning sensation in the mouth (burning mouth syndrome)

  • Increased thirst (especially at night)

  • Swallowing and chewing difficulties (particularly dry foods such as crackers)

  • Speaking difficulties

  • Sore throat

  • Denture sores

People affected by dry mouth also have a higher-than-normal risk of tooth decay and gum disease – according to the Oral Cancer Foundation, xerostomia is a ‘hidden’ cause of gum disease and tooth loss in three out of every 10 adults (ii).

This is thought to be because people with dry mouth don’t produce enough saliva to keep their mouths working properly. Saliva not only keeps your mouth lubricated, it also helps to break down the food you eat, making it easier to swallow. And the saliva in your mouth helps keep your teeth and gums clean and healthy by neutralising the acids made in your mouth when bacteria in dental plaque react with sugars in your food – acids that can irritate gum tissue and destroy tooth enamel, which can lead to tooth decay.

Because of this, people affected by dry mouth are often advised to see their dentist for a check-up more often than those who aren’t affected.

What causes dry mouth?

Xerostomia isn’t an illness in itself, but rather a symptom of one of many different problems and is often associated with a condition called salivary gland hypofunction. This means your saliva glands aren’t working normally.

There are many salivary glands in your head and neck that make saliva, a fluid that contains water, electrolytes (substances in the blood and other body fluids that carry an electric charge, including sodium, calcium and magnesium), mucus and enzymes. The glands release saliva into short tubes called ducts, through which the saliva enters the mouth.

There are up to 1,000 minor salivary glands – most of which are too small to be visible – that are found in the roof of the mouth, the lips, cheeks, nose, sinuses, throat, larynx (voice box) and trachea (windpipe).

The three pairs of major salivary glands are as follows:

Parotid glands

The largest of the major salivary glands, these lie just below and in front of the ears (there’s one on each side) and release saliva through the parotid duct into the inside of your cheeks.

Submandibular glands

Smaller than the parotid glands, the two submandibular glands are found in the floor of your mouth, near the lower jaw. They produce the most saliva – up to 65 per cent(iii).

Sublingual glands

The smallest of the pairs of major salivary glands, these are found just under your tongue. They produce just five per cent or so of the saliva in your mouth(iii).

If your salivary glands are working properly, they produce up to 600ml of saliva a day (i). If you produce lower levels of saliva, you may be diagnosed with salivary gland hypofunction. This condition produces many of the symptoms associated dry mouth, including thick, frothy or stringy saliva, cracked lips and corners of the mouth, bad breath, taste problems, and difficulties with chewing, swallowing, talking and wearing dentures. People with salivary gland hypofunction are also more likely to have tooth decay.

Dry mouth and other medical conditions

Besides salivary gland hypofunction there are several medical conditions that are thought to potentially cause the symptoms of dry mouth, including:

Since dry mouth is associated with several underlying health problems, it’s always advisable to see your GP if the problem persists so that they can rule out any conditions that may be causing it.

Dry mouth and medicines

Many prescription medicines as well as over-the-counter medicines can cause dry mouth. Indeed, experts believe around 400 medicines have reported xerostomia as a side effect, and that prescription medicines may cause around 64 per cent of cases of dry mouth (i).

These include:

  • Antihistamines

  • Decongestants

  • Some blood pressure medicines

  • Anti-diarrhoea medicines

  • Muscle relaxants

  • Urinary continence drugs

  • Some medicines used to treat Parkinson’s disease

  • Some antidepressants

  • Cancer treatments including chemotherapy drugs and radiotherapy to the head or neck (radiation can damage the salivary glands).

If you have an injury to your head or neck, or you’ve had head or neck surgery, it may also cause nerve damage and result in dry mouth. Smoking and chewing tobacco may increase your risk of having dry mouth symptoms too, and you may also be affected if you become dehydrated – for instance if you don’t drink enough fluids, if you exercise in very hot weather or you drink a lot of alcohol.

How to help yourself

If you’re affected by dry mouth there are a few things you can do that may help you feel more comfortable:

  • Try to drink plenty of water, taking regular sips throughout the day. Sucking ice cubes may also be helpful.

  • If your mouth feels particularly dry at night, keep some water by your bed to sip if you wake up.

  • Limit the amount of alcohol, fizzy drinks and drinks that contain caffeine (including tea and coffee) you drink, and avoid drinks that are very hot or very cold.

  • Try chewing sugar-free gum, which can help simulate the production of saliva, or – if you find them helpful – have some sugar-free sweets (chewing gum and sweets that contain a sweetener called xylitol may be particularly useful, as xylitol is thought to help prevent tooth decay).

  • Avoid eating acidic foods – such as lemons – or foods that are spicy, sugary or salty. Meanwhile try adding herbs to your food to make it more palatable if your taste buds have been affected and everything you eat tastes bland.

  • Try to avoid dry foods – soft, moist foods may be the easiest to eat. You could also try rinsing your mouth with water before eating if it helps.

  • Apply lip balm regularly if your lips are also dry.

  • Consider giving up smoking if you’re a smoker (there are lots of products that may help you cope with nicotine cravings, including patches, gum and lozenges).

  • Speak to your GP if you think a prescription medicine is causing your symptoms – however don’t stop taking your medicines without talking to your doctor first.

  • Practice good oral health by brushing your teeth twice a day with a fluoride toothpaste for at least two minutes each time, and cleaning between your teeth with dental floss, tape or interdental brushes once a day.

  • Avoid using toothpastes and other products that contain an ingredient called sodium lauryl sulfate, as some people with dry mouth say they aggravate the condition (sodium lauryl sulfate may also cause mouth ulcers (iv)).

  • If you use mouthwash, avoid using one that contains alcohol.

  • If you wear dentures, always remove them before you go to bed and keep them as clean as possible.

  • Try whenever possible to breathe through your nose rather than your mouth (mouth breathing can be very drying).

  • If you breathe through your mouth when you sleep. consider using a humidifier in your bedroom at night, especially if central heating has made the air very dry (a humidifier can help add moisture to the air in the room).

  • Check your mouth daily for any changes, including red, white or dark patches, ulcers or tooth decay, and see your dentist if you notice anything unusual.

Medical treatments for dry mouth

As well as self-help measures there are treatments you can buy over the counter that may help keep your mouth less dry. These include artificial saliva products such as gels, rinses, sprays, tablets and lozenges, with some also containing ingredients that may help prevent tooth and gum problems. Your dentist or dental hygienist can recommend products that you may find useful, or you could ask a pharmacist for advice about which ones you should try. You can also buy decongestants over the counter at pharmacies if you have a dry mouth because your nose is blocked.

If you’ve tried self-help and pharmacy treatments for a few weeks but your mouth still feels dry, you may want to see your GP. You should also consider seeing your doctor if:

  • You’re having difficulty swallowing, talking or chewing

  • You have sore white patches in your mouth or your mouth is painful, red or swollen

  • You suspect a prescription medicine you’re taking could be causing dry mouth

  • You have a dry mouth as well as any other symptoms

The first thing your GP may do is to test for conditions that may be causing your dry mouth. However, if there’s no evidence of any underlying condition, there are some prescription treatments you could try – or if the problem could be caused by a medicine you’re already taking, your GP may suggest a different dose or an alternative medicine.

Prescription treatments for dry mouth aim to stimulate the production of saliva, and include a medicine called pilocarpine. This is often prescribed to people who have a dry mouth caused by a medication side effect, but it can sometimes cause side effects itself, including diarrhoea, nausea, vomiting and headache.

Pilocarpine may also not be suitable for some people who have asthma, chronic obstructive pulmonary disease (COPD), cardiovascular disease, hyperhidrosis (excessive sweating) and some types of glaucoma.

Meanwhile, for those who experience dry mouth as a result of having radiotherapy of the head or neck, there is some evidence that acupuncture may be helpful (v).

Natural ways to manage dry mouth

If you’re affected by dry mouth, you may find it difficult to follow a varied diet, as some foods may be difficult to chew and swallow. Dry mouth can affect your sense of taste too, which could also have an impact on your appetite. If this is the case, to make sure your body is getting all the essential nutrients it needs to work properly it may be worth considering taking a good-quality, high-strength multivitamin and mineral supplement. Look for an easy-to-swallow tablet or capsule or try a product in a soluble form.

You may also find a live bacteria supplement – such as acidophilus – helpful. For instance, a study that investigated whether live bacteria could help relieve the symptoms of oral thrush in elderly people produced encouraging results, while also discovering that live bacteria may help with dry mouth because they reduce the risk of hyposalivation (vi).

Live bacteria may also be helpful if you have gum disease, which is often found in people with dry mouth. In one study, live bacteria significantly lowered levels of plaque in school children (vii). Researchers elsewhere suggest a particular type of live bacteria called Lactobacillus reuteri may help reduce plaque as well as gum bleeding in people with moderate to severe gingivitis (viii).

Live bacteria supplements are widely available, including products in easy-to-swallow capsules. Meanwhile, foods that contain live bacteria that may be easy for someone with dry mouth to eat include yoghurt, kefir and miso.

Finally, many natural health practitioners also recommend CoQ10 for dry mouth symptoms, as evidence suggests it may help to boost saliva production in people affected by xerostomia (ix). CoQ10 is an important compound made in the body that plays an essential role in energy production, among other things. However, our production of CoQ10 slows down as we get older. There are some food sources of CoQ10 – the richest being organ meats such as liver, as well as beef, pork, chicken and oily fish – but it may be difficult to get enough of it from diet alone.

If you decide to try a CoQ10 supplement, look for one that contains C0Q10 in a natural form, as synthetic supplements may be less effective.

While dry mouth isn’t usually serious it can affect your quality of life, but this guide should help to make it a little easier. For more information on a number of common health conditions, feel free to visit our health library



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  6. , et al. Probiotics reduce the prevalence of oral candida in the elderly--a randomized controlled trial. J Dent Res. 86(2):125-30. Available online:

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Disclaimer: The information presented by Nature's Best is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications.

Our Author - Christine Morgan


Christine Morgan has been a freelance health and wellbeing journalist for almost 20 years, having written for numerous publications including the Daily Mirror, S Magazine, Top Sante, Healthy, Woman & Home, Zest, Allergy, Healthy Times and Pregnancy & Birth; she has also edited several titles such as Women’ Health, Shine’s Real Health & Beauty and All About Health.

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