Dry mouth: what are we talking about?
Dry mouth, or xerostomia, is the feeling of not having enough saliva. It is usually linked to a real drop in saliva production, but not always: some people feel dry even though their glands work normally. In most cases a cause can be identified, and medicines top the list.
Signs that point to a dry mouth:
- scanty, thick or stringy saliva;
- a tongue that sticks to the palate, cracked lips;
- needing a drink to swallow dry food or to talk for a long time;
- waking at night with a parched mouth;
- a burning feeling or altered taste;
- a removable denture that holds less well or rubs.
This is very much a dental matter, because saliva is one of the first lines of defence for the teeth and gums.
Why saliva protects your teeth
Saliva is not just water. It does several jobs you only notice when they stop:
- it neutralises the acids bacteria produce after every sugary snack;
- it supplies the calcium and phosphate that remineralise enamel at the very start of decay;
- it contains antibacterial and antifungal proteins;
- it continuously rinses away food debris;
- it lubricates the soft tissues and helps with speech, swallowing and taste;
- it forms the film that helps a full denture stay in place.
When the flow drops, these defences collapse. Decay then appears in unusual places, especially at the necks of the teeth and on exposed roots, and it progresses faster. Oral thrush (candidiasis), sore spots under dentures and gum inflammation also become more common. How decay develops is explained in our article on tooth decay.
The most common causes
Medicines are the leading cause. Hundreds of drugs can reduce saliva, in particular:
- some antidepressants and anti-anxiety medicines;
- antihistamines (for allergies);
- several blood pressure treatments, including diuretics;
- medicines for urinary incontinence or Parkinson's disease;
- some strong painkillers.
The effect adds up when several treatments are taken together, which is why dry mouth is more common with age. Contrary to a widespread belief, ageing alone has little effect on how well the salivary glands work in a healthy person: it is mainly the illnesses and treatments that come with age.
Other causes worth knowing:
- poorly controlled diabetes, which causes fluid loss and also favours gum infections (see our article on diabetes and gum health);
- mouth breathing, snoring, a frequently blocked nose;
- not drinking enough, heat, smoking, alcohol, a lot of coffee;
- stress and anxiety, which dry the mouth temporarily;
- radiotherapy to the head and neck and some chemotherapy.
Sjögren's syndrome and other medical causes
Sjögren's syndrome is an autoimmune disease in which the immune system attacks the glands that produce saliva and tears. It affects women more often, and it typically combines a persistent dry mouth with dry eyes (a gritty or burning feeling). It may come with joint pain, fatigue or swelling of the salivary glands below the ears.
The dentist may be the first to raise this possibility, but the diagnosis belongs to the doctor: blood tests, a tear test, sometimes a biopsy of a small gland in the lip. This is not something to work out alone online.
Other medical situations can dry the mouth: some thyroid conditions, kidney failure, significant dehydration, infections or stones in the salivary glands. The key point: a dry mouth that sets in without an obvious explanation should be mentioned to your doctor, especially if it comes with dry eyes, intense thirst with frequent urination, or a swollen gland.
What helps day to day
The first rule: never stop a medicine on your own. Talk to the doctor who prescribed it: they can sometimes suggest a similar drug that is less drying, or adjust the dose or the time you take it.
Alongside that, several habits genuinely help:
- sip water throughout the day and keep a glass by the bed;
- chew sugar-free gum or suck sugar-free lozenges (with xylitol, for example), which stimulate saliva as long as the glands still respond;
- cut down on coffee, alcohol and tobacco;
- humidify the bedroom if the air is dry;
- treat a blocked nose so you breathe through it at night;
- protect your lips with a balm;
- choose moist foods and sauces, and avoid dry biscuits as snacks.
On the other hand, avoid sugary sweets to "get the saliva going": they bring relief for a few minutes but feed decay bacteria. Also avoid alcohol-based mouthwashes, which dry the lining of the mouth even more.
Saliva substitutes and fluoride: what your dentist can offer
When dryness persists, saliva substitutes are available as gels, sprays or dedicated rinses. They do not restart the glands, but they lubricate the mouth and make nights, speaking and wearing a denture more comfortable. Many people like a gel at bedtime.
In certain situations, such as Sjögren's syndrome or after radiotherapy, a doctor may prescribe a medicine that stimulates saliva. It does not suit everyone, and its side effects need to be discussed with them.
For the teeth, the aim is to make up for the lost protection:
- a high-fluoride toothpaste on prescription for people at high risk;
- regular application of fluoride varnish at the practice;
- remineralising products based on calcium and phosphate;
- more frequent check-ups to catch early decay at the necks of the teeth;
- treating cavities as soon as they appear, before they reach the nerve;
- monitoring of the gums and any dentures.
Tailored follow-up in Agdal
A dry mouth changes the rhythm and content of dental follow-up. At German Dental Clinic in Agdal, the first appointment starts with a precise list of your medicines and medical history. The dentist then examines the soft tissues, the quality of your saliva, the condition of your gums and the areas prone to decay; digital X-rays complete the examination if needed. If the cause appears to be medical, you are referred to your doctor.
You leave with a concrete prevention plan: which products to use, how often to come back and, if necessary, gum treatment to bring inflammation under control. For someone in Rabat who has lived with a dry mouth for a long time, this assessment often helps slow down the appearance of new cavities. Bring your prescriptions and book an appointment whenever suits you.
Frequently asked questions
Why is my mouth driest at night?
Saliva production naturally falls during sleep. If you breathe through your mouth, snore or have a blocked nose, the air dries the lining further. Some medicines taken in the evening make it worse. A saliva gel at bedtime, a glass of water by the bed and treating the blocked nose often help; mention it to your dentist if it persists.
Can a dry mouth cause tooth decay?
Yes. Without enough saliva, acids are no longer neutralised and enamel struggles to remineralise. Decay then develops faster, often at the necks of the teeth and on the roots, and sometimes under crowns. That is why stronger fluoride protection and more regular check-ups are recommended for people affected.
Can diabetes make your mouth dry?
Yes, especially when it is poorly controlled: the body loses more fluid, which causes thirst and dries the mouth. A dry mouth combined with intense thirst and frequent urination should prompt a visit to a doctor. Diabetes also favours gum infections, which is another reason for regular dental follow-up.
Does chewing gum really help?
Sugar-free gum stimulates saliva as long as the glands can still respond, and it helps neutralise acidity after a meal. It must be sugar-free, otherwise it promotes decay. It is not always advisable if you have jaw pain or grind your teeth, so ask your dentist.
My denture no longer stays in since my mouth became dry. Is that connected?
Quite possibly. A full denture is held partly by the film of saliva between it and the gum. When that film disappears, the denture slips and can rub. A saliva substitute may help, but the fit also needs checking: relining or stabilising the denture with implants can be discussed depending on your situation.
The information on this page is general. Only a consultation allows a diagnosis and a suitable treatment plan.
A question about your own situation?
Dr Fenjero Walid sees patients in Agdal, Rabat, for an assessment and answers that fit your case.
