Dry Mouth (Xerostomia): Symptoms, Causes and Treatment

A dry mouth is uncomfortable, and it raises the risk of dental problems. This guide explains the causes, the effects on your teeth and what helps.

Key points

• Dry mouth (xerostomia) means too little saliva. The NHS says it is rarely a sign of anything serious.¹
• Common causes are dehydration, medicines, mouth breathing at night, anxiety and cancer treatment.¹
• Saliva protects the teeth, so a dry mouth raises the risk of decay. Brush twice a day with fluoride toothpaste and clean between the teeth.¹⁴
• Sip water, chew sugar-free gum, and avoid alcohol, caffeine, smoking and sugary snacks.¹
• Do not stop a prescribed medicine yourself. Ask your doctor.¹

Saliva does a lot of quiet work. It keeps the mouth moist, washes away food, neutralises acid and carries minerals that protect enamel. When there is too little of it, the mouth feels dry and sticky, and the teeth and gums lose a key defence. The medical name is xerostomia, and it is common, particularly in older people and in people who take certain medicines.

What it feels like

• A dry, sticky or rough feeling in the mouth or throat.
• Thick saliva, or less saliva than usual.
• Difficulty chewing, swallowing or speaking.
• A dry tongue that may crack, and cracked lips.
• A changed sense of taste.
• Bad breath.
• Burning or soreness in the mouth.
• Problems with dentures, which may feel loose or sore.

Causes

The NHS says a dry mouth is rarely a sign of anything serious. Common causes include:¹

• dehydration, from not drinking enough, heavy sweating or illness;
• medicines, so check the leaflet for dry mouth as a side effect;
• breathing through the mouth at night, from a blocked nose or sleeping with the mouth open;
• anxiety;
• cancer treatment, such as radiotherapy or chemotherapy;
• oral thrush;
• sometimes, a persistent dry mouth linked to diabetes or Sjögren's syndrome.

Why it matters for your teeth

Without enough saliva, the teeth lose protection. The NHS advises brushing twice a day and using an alcohol-free mouthwash, since dry mouth raises the risk of tooth decay.¹ Decay often starts at the gum line and on root surfaces, and can progress quickly. The gums can also become inflamed, and the mouth is more prone to infections such as thrush. Bad breath is a common effect: the NHS lists dry mouth among the medical causes of bad breath.²

What you can do yourself

The NHS suggests several measures.¹

Do:

• Sip cold water regularly, and keep water by your bed at night.
• Suck on ice cubes or ice lollies.
• Drink cold, unsweetened drinks.
• Chew sugar-free gum or suck sugar-free sweets, which can stimulate saliva.
• Use lip balm if your lips are also dry.
• Brush your teeth twice a day and use an alcohol-free mouthwash.

Avoid:

• Lots of alcohol, caffeine or fizzy drinks.
• Acidic, spicy, salty or sugary foods.
• Smoking.
• Sleeping with dentures in.
• Acidic artificial saliva products if you have your own teeth.
• Stopping a prescribed medicine without medical advice, even if you think it is the cause.

Protecting your teeth

Because dry mouth raises the risk of decay, take extra steps.

• Use fluoride toothpaste. A Cochrane review found that fluoride toothpaste prevents decay, with a larger effect at higher fluoride concentrations.³ Ask your dentist whether a higher-fluoride toothpaste or a fluoride mouthwash is suited to you.
• Brush twice a day, and clean between your teeth every day.⁴
• Limit sugary snacks and drinks, and avoid sipping sweetened drinks.
• Rinse with water after eating.
• See your dentist more often, so decay is caught early.

Treatments

A pharmacist can recommend over-the-counter gels, sprays, tablets or lozenges to keep the mouth moist, though not all suit everyone, so ask for advice.¹ If a blocked nose is contributing, a pharmacist may suggest a decongestant.¹ A doctor can identify the cause and recommend treatment, which may include reviewing your medicines.¹

When to see a doctor or dentist

The NHS advises seeing a GP, which in India means a family doctor, if you have:¹

• difficulty talking or eating;
• a dry mouth that persists after a few weeks of home or pharmacy treatment;
• struggling to eat regularly;
• taste problems that do not go away;
• a painful, red, swollen or bleeding mouth;
• sore white patches in the mouth;
• other symptoms, such as needing to pass urine a lot or dry eyes.

See your dentist for the teeth: a check-up, fluoride advice and early treatment of any decay or gum problem. Our page on gum disease treatment explains what happens if gums are affected, and our guide to cavities describes how decay forms.

Dry mouth and dentures

If you wear dentures, a dry mouth can make them loose and sore, because saliva helps them stay in place. The NHS advises not sleeping with dentures in.¹ Clean them thoroughly, and ask your dentist about adjustments or a different fit.

Dry mouth and bad breath

Dry mouth is among the causes of bad breath that the NHS lists, alongside gum disease, decay and certain foods.² Cleaning the teeth, gums and tongue, drinking water and addressing the dry mouth itself all help. Read our guide on bad breath: causes and what helps.

If you also have gum or tooth problems, see our pages on tooth pain and bleeding gums.

Practical tips for each day

Time	What to do
On waking	Sip water, brush with fluoride toothpaste
During the day	Keep water to hand, chew sugar-free gum after meals
After meals	Rinse with water, and clean between teeth
At night	Keep water by the bed, consider a humidifier, avoid alcohol and caffeine late in the day

What saliva does for your teeth

Saliva is easy to overlook until it is missing. It washes food and acid from the teeth, neutralises acid after you eat, carries calcium and phosphate that help repair early enamel damage, and keeps the gums and tongue moist so you can chew, taste and speak comfortably. A steady flow also limits the growth of the bacteria behind decay and thrush.

When flow drops, these protections weaken together. That is why decay in a dry mouth can start at the gum line and on root surfaces, and why dentists ask about dry mouth even when a patient has come for something else.¹

What to tell your dentist

A dentist can protect your teeth better if they know:

• which medicines you take, and when the dry mouth began;
• whether it is worse at night, on waking or all day;
• whether you breathe through your mouth or snore;
• whether food is hard to swallow or taste has changed;
• how often you have sugary snacks and drinks;
• whether you have had radiotherapy to the head or neck.

With this, the dentist can suggest a fluoride routine, check for early decay at each visit and advise on dentures that have become loose. They may also suggest that you speak to your doctor about the cause.

Dry mouth in older adults

Dry mouth becomes more common with age, mostly because older adults take more medicines. Many everyday medicines list a dry mouth as a side effect, including some for blood pressure, depression, allergies and bladder problems.¹ If you or a relative take several medicines and have a dry mouth, ask the doctor or pharmacist to review them, but do not stop any on your own.

Older adults are also more likely to have exposed root surfaces and dentures, both of which are more vulnerable when saliva is low. Regular dental visits, fluoride toothpaste and careful denture cleaning protect them. Our page on dentures explains how well-fitting dentures are made and kept comfortable.

Myths and facts

Myth: a dry mouth is just a nuisance. It also raises the risk of decay and gum problems, so dental care matters.¹

Myth: sweets keep the mouth moist. Sugary sweets feed decay. Sugar-free sweets or gum are better.¹

Fact: your medicines may be the cause, but do not stop them yourself. Ask your doctor.¹

Frequently asked questions

Is dry mouth a sign of something serious?

The NHS says it is rarely a sign of anything serious, but persistent dry mouth should be checked.¹

Can dry mouth cause cavities?

It raises the risk of tooth decay, which is why careful cleaning and fluoride matter.¹

Does drinking more water fix it?

Water helps with comfort and with dehydration, but it does not replace saliva, so keep up your dental care too.

Which dentist visits do I need?

Your dentist can advise how often, but more frequent check-ups are common if your mouth is dry.

Does dry mouth go away?

It depends on the cause. If it comes from dehydration or a short-term illness, it usually settles. If it comes from a medicine or a long-term condition, it may continue and needs managing.

Is a humidifier useful at night?

It can make a dry bedroom more comfortable, especially if you breathe through your mouth, but it does not replace water, careful cleaning and fluoride.

Can anxiety cause a dry mouth?

Yes. The NHS lists anxiety among the causes, and the dryness often eases when the worry passes.¹

About the author

Sources

1. NHS website. Dry mouth (patient information). Page review date 29 November 2023. https://www.nhs.uk/conditions/dry-mouth/
2. NHS website. Bad breath (halitosis) (patient information). Page review date 5 June 2025. https://www.nhs.uk/conditions/bad-breath/
3. Walsh T, Worthington HV, Glenny AM, Marinho VC, Jeroncic A. Fluoride toothpastes of different concentrations for preventing dental caries. Cochrane Database of Systematic Reviews, 2019;3:CD007868. https://pubmed.ncbi.nlm.nih.gov/30829399/
4. NHS website. How to keep your teeth clean (patient information). Page review date 30 June 2025. https://www.nhs.uk/live-well/healthy-teeth-and-gums/how-to-keep-your-teeth-clean/

Medically reviewed by Dr Natalia DeSilva, BDS, MDS – Oral Medicine and Radiology, on 23 October 2026. General information for patients from Orion Dental Clinic, last updated 23 October 2026. It is not advice for one person, so ask a dentist what suits you. To report an error, contact us.