Dentistry
Cosmetic
Product Reviews
Updated on January 6, 2023
6 min read

Dry Mouth Causes, Symptoms & Treatment

NewMouth is reader supported. We may earn a commission if you purchase something using one of our links. Advertising Disclosure.

What is Dry Mouth?

Dry mouth, also called xerostomia, is a non-life-threatening oral condition. It occurs when the salivary glands in the mouth don’t produce enough saliva to keep the mouth moist.

It’s natural for your mouth to produce less saliva during sleep. This often causes bad breath and xerostomia in the morning. Usually, the sensation goes away or reduces upon waking.

Chronic dry mouth can be attributed to diseases, medications, or problems with the salivary glands. These can cause a drop in saliva production or a change in a person’s saliva content. Children and adults who sleep with their mouths open are also more likely to experience dry mouth. 

Dry mouth reduces a person’s quality of life because it affects simple day-to-day activities, such as tasting, eating, speaking, and swallowing. Untreated xerostomia can cause cavities, dental erosion, and other oral health issues.

According to Dr. Nandita Lilly, an in-house dentist at NewMouth, "dry mouth can result from a myriad of health issues. Your dentist can help you determine the root cause and offer treatment options."

woman drinking water out of glass 1 scaled

Connection Between Saliva and Tooth Decay

Specific components of saliva—such as calcium, phosphate, and bicarbonate—are key to good oral health. Saliva prevents tooth decay by protecting the enamel and controlling acid production caused by dental plaque bacteria.

When acid damages tooth enamel, saliva repairs the tooth's protective surface through remineralization. Saliva also protects against gum disease and cavities.

When saliva production decreases over time, mouth dryness is more likely to occur, which can result in tooth decay or tooth loss.

6 Causes of Dry Mouth

Dry mouth is directly related to the autoimmune destruction of the salivary glands (Sjogren’s syndrome). It can also be indirectly related to cancer treatment, prescription medications, recreational drugs, aging, or other oral health conditions.

Common causes of dry mouth include:

1. Cancer Therapy

Radiation therapy used to treat cancers of the neck, head, face, or salivary glands can increase mouth dryness.

Chemotherapy for any kind of cancer can alter the flow, thickness, and content of saliva. Xerostomia may result from this as well.

2. Prescription Medications

Many prescription drugs can induce oral dryness, including:

  • Antidepressants
  • Anti-anxiety medications
  • ADHD medications
  • Diuretics
  • Muscle relaxants
  • Pain medications
  • Nasal decongestants
  • High blood pressure medications

3. Non-Prescription Drugs

Various non-prescription drugs can contribute to xerostomia:

  • Tobacco slows down how fast your mouth produces saliva, thus leading to dry mouth. Vaping with artificial nicotine may also affect saliva production.
  • Drinking alcohol, especially in excess, can cause dehydration, which can also cause dry mouth.
  • Excessive use of marijuana or amphetamines can also cause dry mouth symptoms.

4. Aging

As people age, the risk of dry mouth increases. Some health conditions associated with aging can contribute to mouth dryness, as can long-term habits such as:

5. Diseases

Various diseases can affect salivary flow and cause dry mouth, including:

  • Sjögren's syndrome, which directly attacks the glands that make tears and saliva
  • HIV/AIDS, which can cause swollen salivary glands, resulting in oral dryness
  • Diabetes
  • Hypertension
  • Lymphoma
  • Hepatitis C

6. Nerve Damage

Nerve damage to the neck or head caused by an injury or surgery can decrease saliva production.

Symptoms of Dry Mouth

Symptoms can develop suddenly or gradually, depending on the patient’s lifestyle. Common signs of dry mouth include:

  • Dry mouth, throat, and tongue
  • Thickened saliva
  • Dry or cracked lips
  • Bad breath, especially in the morning
  • Scratchy or sore throat
  • Hoarseness
  • Abnormal voice changes or difficulty speaking
  • Abnormal changes in taste
  • Difficulty eating, chewing, and swallowing

Diagnosing Dry Mouth

A dentist or medical doctor will listen to your concerns and examine your mouth and throat. They may also order blood tests and imaging scans of your salivary glands.

Diagnostic tests for dry mouth include:

Sialometry

This is a procedure that measures the flow rate of saliva. Collection devices are placed over the salivary duct orifices, and saliva production is stimulated with citric acid and then measured.

Sialography

A radiographic examination of the salivary glands and ducts can identify salivary gland stones and masses.

Biopsy

A sample of salivary gland tissue is taken and examined. This is mostly used to diagnose Sjögren’s syndrome. The doctor may also order a biopsy in cases where malignancy (cancer) is suspected.

Managing and Preventing Dry Mouth

Xerostomia can be reversed or prevented with lifestyle changes. Depending on the condition’s severity, there are natural ways to reduce dry mouth, including:

  • Drinking water regularly to stay hydrated
  • Limiting caffeine and alcohol, which can dehydrate your mouth
  • Avoiding certain medications, such as decongestants and antihistamines
  • Stopping all tobacco and/or nicotine use
  • Breathing through your nose and avoiding mouth breathing
  • Avoiding sugary foods and drinks, such as candy and fruit juices

Professional Treatment for Dry Mouth

Over-the-counter (OTC) and prescription treatments are also available for dry mouth. These products can help stimulate saliva production, and some are intended to bring your saliva content back into balance:

  • Prescription medications that stimulate your salivary glands (such as Salagen or Exovac)
  • OTC artificial saliva substitutes
  • MI Paste, a dental cream designed to restore calcium and phosphate to overly acidic saliva
  • Biotène dry mouth products, which include a paste, lozenge, mouthwash, and spray
  • Fluoride toothpaste or fluoride trays (these can be found OTC or prescribed)
  • Alcohol-free mouthwash
  • Sugar-free gum or hard candy with xylitol (helps increase salivary flow)

You should always speak with a doctor before using any medications or over-the-counter products.

What Can Happen if Dry Mouth Isn’t Treated?

If you have been experiencing chronic dry mouth, see your general dentist as soon as possible. Untreated dry mouth can lead to more serious oral conditions, including:

Cavities

Dry mouth increases the risk of cavities because the lack of saliva causes increased plaque buildup that is harder to remove. 

Dry mouth is more likely to contain different types and increased amounts of bacteria, lowering the mouth's pH levels and making it more acidic. Both conditions can cause damage to dental tissue.

Common treatment options for cavities include fillings, inlays, onlays, and dental crowns. If cavities are left untreated, tooth decay progresses, which can lead to a root canal or tooth loss.

Dental Erosion

One of the most common complications of dry mouth is dental erosion, which occurs when acidic substances wear away tooth enamel. As saliva production decreases, the pH levels in the mouth also decrease. Teeth are less protected from decay-causing bacteria as a result.

Gum Disease

Untreated dry mouth is also a risk factor for gingivitis (minor gum infection) or periodontal disease (severe gum disease that attacks the gums and jawbone). 

Saliva physically flushes away plaque buildup. With dry mouth, plaque adheres to the teeth, making it more difficult to remove. 

Periodontal disease is caused by poor oral hygiene, neglected dental treatment, dry mouth, and/or medications. Symptoms of gum disease include inflamed gums, bleeding gums, and high levels of dental plaque.

Mouth Sores

Mouth sores, ulcers, and canker sores also commonly result from dry mouth.

Oral Thrush (Yeast Infection)

People with dry mouths are more prone to developing oral thrush (also known as candidiasis), an oral yeast infection.

Summary

Dry mouth, or xerostomia, can be caused by changes in the content or flow of your saliva. It may be an occasional symptom or a chronic sensation caused by an underlying medical condition. Various drugs, including prescription medications, can also cause dry mouth.

Xerostomia on its own isn’t life-threatening, but it can contribute to further problems, and in some cases, it can be an indicator of disease. If you experience persistent mouth dryness, see your doctor or dentist as soon as possible.

Last updated on January 6, 2023
6 Sources Cited
Last updated on January 6, 2023
All NewMouth content is medically reviewed and fact-checked by a licensed dentist or orthodontist to ensure the information is factual, current, and relevant.

We have strict sourcing guidelines and only cite from current scientific research, such as scholarly articles, dentistry textbooks, government agencies, and medical journals. This also includes information provided by the American Dental Association (ADA), the American Association of Orthodontics (AAO), and the American Academy of Pediatrics (AAP).
  1. Tucker, Abigail S., and Isabelle Miletich. “Salivary Glands: Development, Adaptations, and Disease.” Journal of Anatomy, 2010.
  2. Farsi, N.M. “Signs of oral dryness in relation to salivary flow rate, pH, buffering capacity and dry mouth complaints.” BMC Oral Health, 2007.
  3. Mortazavi, H, et al. “Xerostomia due to systemic disease: a review of 20 conditions and mechanisms.” Annals of medical and health sciences research, 2014.
  4. Napeñas, J.J., et al. “Diagnosis and treatment of xerostomia (dry mouth).” Odontology, 2009.
  5. Villa, Alessandro, et al. “Diagnosis and management of xerostomia and hyposalivation.” Therapeutics and clinical risk management, 2014.
  6. Billings, Monisha, et al. "Significance and Implications of Patient-reported Xerostomia in Sjögren's Syndrome: Findings From the National Institutes of Health Cohort." EBioMedicine, 2016.
linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram