Dealing with a Dry Mouth, and the Thyroid Disease Link

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Dry mouth, known medically by the term xerostomia, is a medical condition that doesn't receive a great deal of attention. Dry mouth is also referred to colloquially as pasties, cottonmouth, drooth, doughmouth, and des.

If you're among the thousands of people who suffer from chronic dryness of the mouth, you know how unpleasant, annoying and even dangerous it can be. 

"[Dry mouth] can seriously mar the quality of life," notes Dr. Bruce Baum of the National Institutes of Health (NIH), an expert on salivary and saliva-producing gland disorders.

Says Dr. Baum:

Dry mouth can lead to cavities, mouth sores and infections; chewing, speaking and swallowing difficulties; and other problems. The good news is that there are therapeutic options that can often successfully deal with this symptom.

What Causes Dry Mouth?

Contrary to popular belief, dry mouth is not a normal part of aging. Dry mouth can develop when your salivary glands don't work properly. There are a number of reasons why your salivary glands may not work properly and cause dry mouth symptoms. These include:

Mouth breathing: Breathing through the mouth while awake or asleep, and sleep apnea, are both associated with dry mouth

Smoking: Both cigarettes and cigars

Recreational drug use: Including methamphetamine, cannabis, heroin, and hallucinogens

Medications: There are more than 500 prescription and over-the-counter medications are xerogenic, meaning that they cause dry mouth as a known side effect.

You can see a 23-page list of xerogenic medications here.

Radiation and chemotherapy: When you have cancer, treatments such as radiation and chemotherapy are known to cause long-term dryness in your mouth. 

Some rare conditions: Rare conditions, including sarcoidosis or amyloidosis, can cause dry mouth.


More common conditions: A number of common health conditions can cause dry mouth, including upper respiratory infections, dehydration, diabetes, AIDS, Parkinson's disease, and especially autoimmune conditions such as Sjögren's (pronounced "show-grens") syndrome, a disorder in which the person's own immune system targets moisture-producing glands and causes dryness in the mouth and eyes. 

Thyroid disease: Dry mouth can be a symptom of both hypothyroidism and hyperthyroidism, even when treated.

Dry Mouth Symptoms

Beyond simply being a nuisance, dry mouth can lead to additional problems, including the ability to swallow, enjoy food, and, in severe cases, problems with communication. When it lasts for several days or weeks, dry mouth is often a symptom of an underlying disease. Symptoms include: 

  • A viscous and pasty mouth
  • Ulcers or sores on the inside of your mouth 
  • Infections of the mouth and on the tongue, especially thrush and other fungal infections
  • Dental cavities
  • Gum disease
  • Chronic bad breath
  • Reduced sense of taste
  • Chapped, splitting or cracking lips, especially at the corners of your mouth
  • Splitting and cracking of linings of your cheeks and lips
  • Increased thirst
  • Difficulty swallowing and chewing dry foods
  • Painful tongue
  • Sialadenitis, an infection of your salivary glands
  • Sore throat
  • Sticky or stringy saliva
  • Problems with dentures

Treating Dry Mouth

There is currently no cure for severe salivary gland dysfunction. Dr. Baum and his colleagues have been working on novel treatment approaches, including using gene transfer methods and trying to develop an artificial salivary gland. "Based on the results of our studies thus far," Dr. Baum says, "I am optimistic that we or others will be able to help these patients in the not too distant future." However, such therapies are still being tested in the laboratory and are not yet ready for patients.

Since many drugs, such as those used to treat high blood pressure and depression, cause dry mouth, talk to your doctor or dentist about the medicines you are taking: You may need to have your dosage adjusted or your medicine changed.

Some other approaches to help people with dry mouth include:.

  • Saliva substitutes, such as SalivaMAX, artificial salivas 
  • Saliva stimulants, such as tart gums and candy
  • Drinking lots of fluid to keep your mouth moist 
  • Putting a humidifier in your bedroom.
  • Ask your doctor or dentist about prescription medicines that may help the salivary glands function better, Avoiding tobacco, alcohol, and caffeine, all of which dry out the mouth. 

A Word from Verywell

If your chronic dry mouth is the result of undiagnosed thyroid disease, your first step is to get properly diagnosed and treated. Keep in mind that if your thyroid treatment is not optimal, even after treatment, you may still experience dry mouth symptoms. In many cases, proper diagnosis and optimal thyroid treatment can resolve your xerostomia. 


Baum, Bruce. "Gene Therapy for Salivary Gland Shows Promise." NIH Research Matters. December 3, 2012. 

Delli K, et al. "Xerostomia." Monogr Oral Sci. 2014;24:109-25. doi: 10.1159/000358792. Epub 2014 May 23. Review. PMID: 24862599

Plemons JM, et al. "Managing xerostomia and salivary gland hypofunction: executive summary of a report from the American Dental Association Council on Scientific Affairs." J Am Dent Assoc. 2014 Aug;145(8):867-73. doi: 10.14219/jada.2014.44.

Tanasiewicz M, et al. "Xerostomia of Various Etiologies: A Review of the Literature."
Adv Clin Exp Med. 2016 Jan-Feb;25(1):199-206. doi: 10.17219/acem/29375. Review.
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