Dry Mouth: 7 Common Causes & How to Treat It

Dry mouth is a condition caused by reduced saliva production, which can occur at any age but is more common in older women. It may be temporary or persistent and is often linked to factors like dehydration, medications, or underlying health conditions.

Dry mouth, also known as xerostomia, can be associated with symptoms such as bad breath, cracked lips, difficulty swallowing, and a higher risk of cavities or oral infections. Common causes include nutritional deficiencies, autoimmune diseases, hormonal changes, thyroid problems, and certain treatments like radiation therapy.

Treatment for dry mouth focuses on increasing saliva production through simple measures like hydration, sugar-free gum, and oral care, or with medications when needed. Identifying the underlying cause is essential, as persistent dry mouth may require evaluation by a healthcare provider for proper management.

What causes dry mouth?

The most common causes of dry mouth include:

1. Nutritional deficiencies 

Deficiency in vitamin A or B-complex vitamins can dry out the mouth's mucous membranes, causing mouth and tongue sores. These vitamins are found in foods like fish, meat, and eggs.

Learn more about vitamin B12 deficiency and symptoms to look out for.

How to treat: A registered dietitian can identify your specific nutritional deficiencies and recommend appropriate supplements and dietary changes. They will provide tailored food recommendations and portion sizes to address the deficiency and relieve symptoms.

2. Autoimmune diseases

Autoimmune diseases occur when the immune system produces antibodies that mistakenly attack the body’s own healthy cells, causing inflammation. In some cases, these antibodies can affect the salivary glands, reducing saliva production and leading to dry mouth.

Autoimmune diseases that can cause dry mouth include lupus and Sjögren syndrome. Sjögren syndrome can also cause a gritty or sandy feeling in the eyes, and both conditions can increase the risk of cavities and infections like conjunctivitis.

How to treat: Treatment should be guided by a rheumatologist, who may recommend artificial saliva to relieve dry mouth and prescribe other treatments based on the underlying autoimmune condition.

3. Medications

Some medications can cause dry mouth, including antidepressants, diuretics, antipsychotics, blood pressure medications, and some cancer treatments.

Cancer treatments, such as radiation therapy, can also cause dry mouth as a side effect. This is more common when radiation is applied to the head or neck area and may occur with gum sores, depending on the radiation dose.

How to treat: The prescribing doctor should be consulted to assess whether dry mouth is related to medication use. If needed, the doctor may adjust the dose or recommend an alternative treatment.

4. Thyroid problems

Hashimoto’s disease is an autoimmune condition in which antibodies attack the thyroid, causing inflammation. This can affect thyroid hormone levels and may lead to symptoms that develop gradually, including dry mouth.

Read more about other symptoms of thyroid problems. 

How to treat: Treatment should be guided by an endocrinologist, who may recommend hormone replacement therapy with levothyroxine if hypothyroidism is present. In some cases, surgery to remove the thyroid may be necessary.

5. Hormonal changes

Hormonal changes, especially during menopause and pregnancy, can affect saliva production and lead to dry mouth.

During pregnancy, dry mouth may happen when fluid intake is too low, as the body needs more water to support placenta formation and amniotic fluid. Therefore, pregnant people may need to drink more water throughout the day to stay hydrated.

How to treat: It is important to drink water regularly, taking small sips throughout the day to keep the mouth moist. People with menopause-related dry mouth should consult a doctor, as hormone replacement therapy (HRT) may be recommended in some cases.

6. Respiratory problems

Some respiratory problems, such as a deviated septum or airway obstruction, can make a person breathe through the mouth. Over time, mouth breathing can increase the risk of infections, as the nose is no longer filtering the air properly, and may also lead to dry mouth and bad breath.

How to treat: An otorhinolaryngologist (ENT specialist) should be consulted to diagnose the respiratory problem and recommend the most appropriate treatment. A deviated septum, for example, may be corrected with surgery, while airway obstructions should be carefully assessed and treated based on the cause.

7. Lifestyle habits

Lifestyle habits, such as smoking, eating too many sugary foods, or not drinking enough water, can lead to dry mouth and bad breath. Over time, these habits can also increase the risk of health problems, such as emphysema in smokers or diabetes in people with a high sugar intake.

Dry mouth is common in people with diabetes and may happen due to polyuria, which is frequent urination that can lead to dehydration. In these cases, increasing water intake may help, but a doctor may need to review medications and overall diabetes treatment.

How to treat: It is important to drink more water, avoid smoking, and limit sugary foods. People with diabetes should follow the treatment plan recommended by their endocrinologist, which may include oral diabetes medications or insulin.

Other symptoms 

Dry mouth can cause symptoms such as dry or cracked lips, trouble tasting food, bad breath, and headaches.

According to the National Institute of Dental and Craniofacial Research, dry mouth can make chewing, swallowing, and speaking difficult and may increase the risk of tooth decay and oral infections. Persistent cases may also lead to bad breath and infections caused by Candida albicans.

A primary care provider should be consulted if dry mouth is persistent or occurs with other symptoms. Depending on the suspected cause, a referral may be made to an endocrinologist, gastroenterologist, or other specialist.

Dry mouth treatment

One of the best ways to treat dry mouth is to drink plenty of water throughout the day. According to the American Dental Association, sugar-free candy or gum, artificial saliva, and oral rinses may also help relieve dry mouth.

Other ways to relieve dry mouth include:

• Sucking on ice chips
• Eating acidic or citrus foods
• Having fluoride applied by a dentist
• Brushing the teeth, flossing, and using mouthwash at least twice per day
• Drinking ginger tea

Artificial saliva may help relieve dry mouth and make chewing, speaking, and swallowing easier. A doctor may also prescribe medications, such as pilocarpine, to increase saliva production.

It is also important to avoid licking the lips, as this can make dryness worse. Instead, the lips can be kept hydrated with lip balm, moisturizer, or coconut oil.