The Connection Between Thyroid Disease and Dry Mouth

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Dry mouth, known medically by the term xerostomia, is more than simply a nuisance. It can impair a person's ability to swallow, enjoy food, and in severe cases, talk.

Moreover, a pasty, dry mouth can lead to infections, mouth sores, cavities, gum disease, and chapped, splitting, or cracking lips.

While everyone gets a dry mouth now and then, when it lasts for several days or weeks, your dry mouth may be a symptom of an underlying disease or health problem.

Causes of Dry Mouth: Thyroid Disease and More

A dry mouth develops when your salivary glands are not working properly, and there are a number of reasons why this may occur.

One major health culprit of a dry mouth is Sjögren's syndrome, an autoimmune condition in which a person's own immune system targets moisture-producing glands and causes dryness in the mouth and eyes. Dry mouth can also be a symptom of both hypothyroidism and hyperthyroidism, even when treated.

Interestingly, Sjögren's syndrome and a health condition called burning mouth syndrome are more common in people with thyroid disease. Burning mouth syndrome causes burning pain in the mouth, and often a dry mouth, along with a salty or metallic taste disturbance.

Other health problems that may lead to a dry mouth include:

  • Upper respiratory infections
  • Dehydration
  • Diabetes
  • AIDS
  • Parkinson's disease 
  • Sleep apnea

Smoking too and recreational drug use (including methamphetamine, cannabis, heroin, and hallucinogens) can lead to chronic dry mouth.

Lastly, it's important to note that medications, like certain antidepressants, high blood pressure drugs, chemotherapies, and cold medicines are a big contributor to dry mouth (sometimes the primary cause). In fact, there is believed to be over 500 prescription and over-the-counter medications that are xenogenic, meaning dry mouth is a known potential side effect.

Treatment of Dry Mouth

The first step is to determine with your doctor the "why" behind your (or your loved one's) dry mouth. 

Since many medications cause dry mouth, it's sensible to talk to your doctor or dentist about the medicines you are taking. You may need to have your dosage adjusted or your medicine changed.

Treating the Underlying Disease

If your doctor suspects that an underlying health problem could be causing your dry mouth, he may order some tests, like blood and urine tests, an eye test (in Sjögren's syndrome, a person's eyes do not make a normal amount of tears), an MRI of your salivary glands, and/or a biopsy of the salivary gland (a small piece of tissue is removed from the inside of your lip).

If a diagnosis is made, treatment of that underlying condition is paramount to managing your dry mouth; although keep in mind, it may not be curable. 

If your chronic dry mouth is believed to be the result of undiagnosed thyroid disease, your first step is to get diagnosed and treated. In many cases, proper diagnosis and optimal thyroid treatment can resolve your xerostomia. 

Other Remedies

Besides treating the underlying condition, some other approaches to ease a dry mouth, include:

  • Taking saliva substitutes, such as SalivaMAX, artificial salivas
  • Taking sugar-free saliva stimulants, such as tart gums and candy.
  • Drinking lots of fluid to keep your mouth moist. 
  • Putting a humidifier in your bedroom.
  • Undergoing regular preventive dental care (special toothpaste and fluoride applications may be recommended).
  • Avoiding tobacco, alcohol, carbonated beverages, juices, and caffeine, all of which may dry out the mouth. 

A Word from Verywell

While having a dry mouth is unpleasant and poses health concerns, the good news is that with guidance from your doctor, most people can discover the culprit (or culprits) behind it and manage well with proper dental care and saliva-stimulating strategies.

However, if your mouth continues to be dry and problematic, consider obtaining a second opinion and/or seeking care from a dentist who has experience treating dry mouth.

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