Dry Mouth: 7 Causes & What to Do

Clinical review: Cassiano Scapini
July 2022

Having a dry mouth is characterized by a decreased or malfunctioning in the production of saliva. It can occur at any age, but is most common in older women.

Dry mouth, which is also referred to as xerostomia, can occur for many reasons. Treatment is generally aimed at increasing saliva production through simple measures or through prescription medication.  

Dry mouth when waking up may be a sign of mild dehydration, and therefore you should increase your water intake. If this symptom persists, however, you should see a doctor for assessment. 

Imagem ilustrativa número 1

Dry mouth causes

The most common causes of dry mouth include:

1. Nutritional deficiencies 

A lack of vitamin A or B-complex vitamins can dry the mucous membranes in the mouth, leading to wounds in the mouth and on the tongue. 

B-complex vitamins and vitamin A can be found in foods like fish, meat and eggs. Learn more about vitamin B12 deficiency and the symptoms associated with it. 

2. Autoimmune disease

Autoimmune diseases are caused by the production of antibodies that attack the person’s own body, leading to widespread inflammation. Some antibodies may affect specific glands in the body, like the salivary glands, which can lead to decreased saliva production and dry mouth. 

Some autoimmune disease that can cause dry mouth are systemic lupus erythematosus and Sjögren syndrome, which can also cause the sensation of sand in your eyes. These conditions are associated with a higher risk of infections liike cavities and conjunctivitis. 

3. Medications

Some medications can cause dry mouth, like antidepressants, diuretics, antipsychotics, antihypertensives and cancer medication. 

Certain treatments, like radiation therapy for cancer, can lead to dry mouth as a side effect. This can especially happen when radiation is applied to the head or neck, which can also cause wounds on the gums, depending on the radiation dose.

4. Thyroid problems

Hashimoto’s disease is characterized by the production of antibodies that attack the thyroid and cause inflammation. This leads to a hyperthyroid state, which is then followed by hypothyroidism, The signs and symptoms of a thyroid problem can emerge gradually and include dry mouth. 

Read more about other symptoms of thyroid problems

5. Hormonal changes

Hormonal changes, especially during menopause and pregnancy, can cause a series of imbalances that can affect saliva production and lead to dry mouth.

Dry mouth during pregnancy can occur due to inadequate fluid intake, as intake should increase during this time. Sufficient daily water is important for placenta formation and amniotic fluid. Therefore, if you were already drinking about 2 L of water per day, you should aim to increase your water intake to 3 L per day. 

6. Respiratory problems

Some respiratory problems, like a deviated septium or an airway obstruction, can force you to breathe through your mouth. After many years of this type of breathing, it is possible to experience changes to facial anatomy and a higher risk for infections (because the nose is no longer filtering inhaled air). The constant entry and exit of air through the mouth can lead to dry mouth and bad breath. 

7. Lifestyle habits

Lifestyle habits, like smoking, eating sugary food or not drinking enough water can lead to dry mouth and bad breath. These habits can also cause more serious diseases, like emphysema in smokers, or diabetes in people who consume sugary foods. 

A dry mouth in the context of diabetes is very common, and can be a result of polyuria (frequent urination). You can prevent dry mouth in this case by increasing you water intake, however the doctor may need to evaluate your medications and treatment, depending on the severity of this side effect. 

How to treat dry mouth

One of the best way to treat dry mouth is to drink plenty of water throughout the day. You can also stimulate saliva secretion by: 

  • Sucking on hard candy or chewing sugar-free gum 
  • Eating more acidic or citric foods
  • Applying fluoride at the dentist
  • Brushing you teeth, using dental floss and using a mouthwash at least twice per day 
  • Drinking ginger tea  

Artificial saliva can also help to combat symptoms of dry mouth and help with chewing. The doctor can additionally prescribe medications like sorbitol or policarpine. 

Another important consideration is to avoid licking your lips, as this can dry out your lips and mouth. You should instead hydrate your lips by using a moisturizer, a hydrating chapstick, or coconut butter.

Signs and symptoms of dry mouth 

Having a dry mouth can occur with other symptoms, like dried and cracked lips and difficulties speaking, chewing, tasting and swallowing. People with persistent dry mouth have a higher probability of getting cavities and generally have foul breath. They may also experience headaches and an increased risk for oral infections, mostly caused by Candida Albicans.  

You should see your family doctor if you experience dry mouth. He or she may refer you to an endocrinologist or gastroenterologist, depending on the underlying cause. 

Was this information helpful?

Edited by Tua Saude editing team in July 2022. Clinical review completed by Cassiano Scapini - Dentist in July 2022.
Clinical review:
Cassiano Scapini
Graduated in Dentistry by the UFRGS in 1988 and member no. 2575 of the OMD, Portugal.