It's normal to occasionally have a dry mouth if you’re dehydrated or feeling nervous, but a persistently dry mouth can be a sign of an underlying problem.
You should see your dentist or GP if you have an unusually dry mouth (known as xerostomia) so they can try to determine the cause.
What can cause a dry mouth?
A dry mouth can occur when the salivary glands in your mouth don't produce enough saliva.
This is often the result of dehydration, which means you don’t have enough fluid in your body to produce the saliva you need. It's also common for your mouth to become dry if you're feeling anxious or nervous.
A dry mouth can sometimes be caused by an underlying problem or medical condition, such as:
- medication – many different medications can cause a dry mouth, including antidepressants, antihistamines and diuretics; check the leaflet that comes with your medicine, or find it in the medicines section to see if dry mouth is listed as a side effect
- a blocked nose – breathing through your mouth while you sleep can cause it to dry out
- diabetes – a lifelong condition that causes a person's blood sugar level to become too high
- radiotherapy to the head and neck – this can cause the salivary glands to become inflamed (mucositis)
- Sjögren's syndrome – a condition where the immune system attacks and damages the salivary glands
If you see your dentist or GP, let them know about any other symptoms you're experiencing and any treatments you’re having, as this will help them work out why your mouth is dry.
What problems can a dry mouth cause?
Saliva plays an important role in keeping your mouth healthy. If you have a dry mouth, you may experience a number of other problems too, such as:
- a burning sensation or soreness in your mouth
- dry lips
- bad breath (halitosis)
- a decreased or altered sense of taste
- recurrent mouth infections, such as oral thrush
- tooth decay and gum disease
- difficulty speaking, eating or swallowing
It’s important to maintain good oral hygiene if you have a dry mouth to reduce the risk of dental problems. You should also see a dentist regularly, so they can identify and treat any problems early on.
Treating a dry mouth
Treating the underlying cause
If your doctor or dentist is able to determine what's causing your dry mouth, treating this may improve your symptoms.
For example, if medication is suspected as the cause of your dry mouth, your doctor may reduce your dose or suggest trying an alternative medication.
Some of the conditions mentioned above have specific treatments, such as nasal decongestants for a blocked nose and insulin for diabetes.
Things to try yourself
There are simple measures you can try to help keep your mouth moist. For example, it may help to:
- increase your fluid intake – take regular sips of cold water or an unsweetened drink
- suck on sugar-free sweets or chew sugar-free gum – this can stimulate your salivary glands to produce more saliva
- suck on ice cubes – the ice will melt slowly and moisten your mouth
- avoid alcohol (including alcohol-based mouthwashes), caffeine and smoking – these can all make a dry mouth worse
Saliva substitutes and stimulants
If the measures above don’t help, your dentist, GP or specialist may suggest using an artificial saliva substitute to keep your mouth moist. This may come in the form of a spray, gel or lozenge. Use it as often as you need to, including before and during meals.
If your dry mouth is caused by radiotherapy or Sjögren's syndrome, a medication called pilocarpine may be prescribed. This is taken as a tablet several times a day to help stimulate your salivary glands to produce more saliva.
However, pilocarpine isn't suitable for everyone, as it may cause side effects, such as sweating or headaches.