Dry Mouth: Consequences, Causes, and Treatments

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Hi, I’m Dr. B, practicing functional dentist for 35 years. I graduated from the Dugoni School of Dentistry in San Francisco, CA in 1987 and am a member of the American Academy of Dental Sleep Medicine (AADSM), Academy of General Dentistry (Chicago, IL), American Academy for Oral Systemic Health (AAOSH), and Dental Board of California. I'm on a mission to empower people everywhere with the same evidence-based, easy-to-understand dental health advice that my patients get. Learn more about Dr. B

Whether you recently tried a new mouthwash that is high in alcohol content, just ate a sleeve of saltine crackers, or are going through cancer treatments, the resulting dry mouth can be uncomfortable and embarrassing. Worse yet, that sticky feeling that isn’t easily fixed with a glass of water isn’t just annoying. Dry mouth can have a big impact on oral, dental, and even your overall health.

Known medically as xerostomia, dry mouth reportedly affects around 10 percent of the population. (1) I suspect it’s much higher, though, as many people don’t realize they have it. The term “dry mouth” may conjure thoughts of a completely barren oral cavity that produces no moisture whatsoever. But even low production of saliva (less than the 1 to 2 liters produced by a healthy mouth) is cause for concern.

Trained dentists can spot someone struggling with this condition, often before the patient realizes they’re experiencing it. And this is important because, when left untreated, dry mouth can wreck the oral microbiome, ultimately leading to cavities, bad breath, and other oral issues.

Here’s how:

Consequences of Dry Mouth

Cavities: You may think that poor brushing and flossing habits (or consumption of too many cookies and candies) is the primary cause of cavity formation, but that distinction actually belongs to dry mouth.

Cavities are holes in your teeth that are formed by bacteria that excrete acids onto the teeth. These acids then eat away at enamel, causing decay. In a healthy mouth, saliva protects against these acids and prevent cavities by washing away harmful bacteria and supporting remineralization.

Dry mouth obviously disrupts this process by not allowing teeth to bathe in saliva, and it can also cause the pH of the mouth drop into the acidic zone, which further promotes cavities by allowing harmful bacteria to multiply. Even a few hours of dry mouth can disrupt the mouth’s microbiome and increase your chances of a cavity.

Imbalanced oral microbiome: Just like your gut, your mouth has a microbiome that affects your health. When the bacteria in your mouth are balanced, it promotes healing, remineralization, and an overall happy mouth. But when the oral microbiome disrupted due to dry mouth, leading to an overgrowth of bad bacteria and a decrease in the numbers of beneficial bacteria, the risk for infection, cavities, and oral yeast infection (thrush) goes up.

Digestive issues: Speaking of your gut, it’s important to note that digestion starts in your mouth. If you don’t have adequate saliva to start breaking down food into small enough pieces, and if you have an excess of bad bacteria in your mouth due to an acidic oral pH level, the rest of your digestive system may suffer. And because what happens in the mouth happens in the body, an abundance of bad bacteria in your mouth can even affect the balance of bacteria in your gut.

Mouth sores: Without enough saliva to neutralize the acids in your mouth and hydrate delicate oral tissue, painful mouth sores can occur. These are especially common in cancer patients.

Poor nutrition: If you’re having trouble swallowing because of uncomfortable dry mouth, you may be less interested in eating, causing you to consume foods that contain important nutrients.

Causes of Dry Mouth

As I mentioned, dry mouth can be caused by a variety of factors—some that are preventable, lifestyle factors, and others that are less preventable and are a result of medical diagnosis or prescription drugs. Ultimately, understanding the cause can help you understand which treatment options are available.

Lifestyle causes of dry mouth

Mouth breathing: Many people breathe through their mouth without realizing it, especially at night. The salivary glands slow production while you’re sleeping anyway, but breathing through your mouth only exacerbates the dryness. In the morning you may find it difficult to talk or swallow and have an urge to drink water immediately.

You may mouth breathe out of habit, or because of an underlying issue like sleep apnea, allergies, an illness, a deviated septum, stress, or the shape of your nose. A formal sleep study is a good way to determine the root cause of your sleep issues, but they can be expensive and inconvenient. As an alternative, an at-home sleep test may be helpful.

Smoking or chewing tobacco: Smoking or chewing tobacco can decrease saliva production as well as upset the natural bacteria in the mouth, causing a further increase in dry mouth symptoms. (2)

Stress: In recent years we’ve learned that stress can contribute to a multitude of health conditions, including weight gain, insomnia, and high blood pressure. And as it turns out, stress can also cause temporary dry mouth. (3) This is important to keep in mind if you have a sudden onset of dry mouth that lasts only a few days at a time. However, if the condition is persistent, there may be another underlying cause.

Dehydration: Dehydration is a condition that many people don’t identify until it has become severe. in fact, science says that if you feel thirsty, you’re already dehydrated. (4) Athletes, in particular, are at risk for dehydration that can cause dry mouth, as are diabetics.

Medical causes of dry mouth

Chemo and radiation: Both chemo and radiation can decrease how much saliva your salivary glands are able to produce.

Prescription drugs: More than 1,800 prescription drugs, including everything from antidepressants to antihistamines and cannabinoids, list dry mouth as a known side effect. (5)

Diseases: A number of diseases are known to cause dry mouth as a common symptom, including Sjögren’s syndrome, HIV/AIDS, diabetes, Alzheimer’s, and rheumatoid arthritis.

Nerve damage: Head or neck injuries that included nerve damage may also impact the salivary glands and can, as a result, cause persistent dry mouth.

Dry mouth symptoms

Obviously, the causes mentioned above don’t always result in dry mouth, and sometimes a little dryness isn’t a cause for major concern.

So, how do you know if you’re just feeling a little parched or if you have dry mouth? Here are a few of the symptoms to look for:

Persistent dry mouth: This may seem obvious, but a persistent dry mouth (that is, one that isn’t directly related to a certain food or drink and then easily remedied with water) is often the most reliable and easily identifiable sign of a serious issue.

In addition to the mouth feeling dry, saliva that is thicker than normal, or a mouth that feels sticky can be signs of dry mouth.

Difficulty swallowing or speaking: Without sufficient saliva, swallowing can become a challenge, since there isn’t enough fluid to sufficiently move through the throat. Additionally, dryness can cause your tongue to stick to the sides and roof of your mouth, slowing down your rate of speech.

Increased thirst: A dry mouth can be uncomfortable, and often people try to compensate by drinking more liquids trying to soothe it. if you seem to be reaching for water or other beverages simply to improve your mouth-feel, there may be cause for concern.

Increased cavity rate: If you show up for a dentist appointment and find that you have a ton of new cavities, it could be because you aren’t producing enough saliva. A dry mouth can cause an imbalance in the oral microbiome, allowing harmful, cavity-causing bacteria to flourish.

Digestive issues: Digestion starts in the mouth, and if you don’t break down your food well in this initial stage, your digestive system won’t be able to do its job as well. Dry mouth reduces saliva production, and it is the enzymes in saliva that help break down food in the mouth.

Bad breath: Inadequate amounts of saliva can cause certain bacteria to flourish, which can lead to an overall unhealthy mouth in the form of inflammation or tooth decay, and thus bad breath.

Change in sense of taste: A lack of saliva can not only make it difficult to eat dry foods like crackers and breads, but it can also make it harder to taste certain flavors. (6) The tongue’s taste buds are responsible for distinguishing different tastes (including sweet, sour, bitter, salty, and umami) and a dry mouth prevents the taste buds from functioning effectively.

How to Treat Dry Mouth

Not that you’re aware of the symptoms that may identify dry mouth, it’s important to discuss ways to treat the condition before major issues arise.

Learn to nose breathe: If you’re otherwise healthy, there’s a good chance that your case of dry mouth is related to mouth breathing. And if you’ve been mouth breathing for a long time—and have ruled out causes like sleep apnea or allergies—you may want to make an appointment with a myofunctional therapist.

A myofunctional therapist can work with you to retrain the muscles of your mouth and lips to rest comfortably in a closed position. Your therapist may also work with you to find the root cause of your mouth breathing if you’ve struggled to uncover it on your own.

Try mouth taping: If you’ve ever been told that you snore at night, or if you know that you’re a mouth breather, mouth taping may be a good option for you.

Mouth taping is exactly what it sounds like—the mouth is taped shut at night to encourage breathing through the nose. If you find that you can’t get the tape to stay on overnight, it’s a good indicator that you’re struggling to breathe through your nose and it may be worth speaking with an ear, nose, and throat specialist to find out why—especially since mouth breathing is a primary cause of dry mouth.

Avoid foods that dry out the mouth: Crusty bread, acidic foods like vinegars and citrus fruits, salty foods, spicy foods, sugary foods and beverages, difficult-to-chew meats, and dry foods like crackers and chips are all difficult to eat when you have dry mouth. Additionally, these foods also make the condition worse.

Instead of eating these types of foods, focus on moist, lukewarm dishes, and consider following an anti-cavity diet to keep your mouth healthy while you solve your dry mouth problem.

Hydrate: The average person should drink eight 8-ounce glasses of water a day, and serious athletes will likely need more. Avoid hot beverages, which can damage tissue in the mouth, as well as beverages that further dehydrate, including coffee and caffeinated teas.

Ask to switch of change dosage of prescription medicines: If you suspect your medication may be behind your dry mouth, speak to your doctor about changing your prescription or decreasing the amount of medicine you’re taking until your dry mouth symptoms decrease.

Try artificial saliva: There are products on the market that help to relieve the symptoms of dry mouth. I recommend the Biotene gel, which you squeeze onto the tip of your tongue and swish around in your mouth. The gel doesn’t stimulate saliva, but rather mimics the feel of saliva in the mouth, providing relief. Patients undergoing chemo or radiation or diabetics dealing with chronic dry mouth may find it useful. It’s important to note, however, that Biotene is not a solution and must be reapplied regularly.

Final Thoughts

Dry mouth can be caused by mouth breathing, medications, and certain foods and drinks. No matter the cause, though, dry mouth can contribute to ongoing oral and dental problems, including cavities and bad breath.

Whether your condition is a mild discomfort or a deeply painful experience, it’s worth talking to your doctor and dentist. It could be a crucial step in keeping your mouth—and your whole body—healthy.

Simple solutions to address this condition include mouth taping, hydrating, and avoiding foods and drinks that are especially drying in the mouth.

Learn More: The Mouth-Body Connection: 6 Ways Oral Health Impacts Overall Health