Dry Mouth: Symptoms, Causes, and How to Treat It

At some point, you've probably felt "cotton mouth," that dryness in your oral cavity that makes you suddenly thirsty. Dry mouth, also called xerostomia, is the feeling of oral dryness caused by too little saliva or saliva that isn't working well enough. It can happen even when some saliva is still present, because the issue may be saliva quality or flow rather than a total absence of saliva.

Estimates of how many people are affected vary widely depending on how studies define and measure the condition, with some research reporting a range as broad as roughly 1% to 65% of the general population. More consistently, dry mouth is thought to affect somewhere around 10% to 30% of adults, and it's more common in older adults, partly because many take multiple medications that can reduce saliva flow.

A lack of adequate saliva can make it harder to speak, chew, and swallow, and it raises your risk of tooth decay, gum disease, bad breath, and mouth sores. This guide covers the symptoms, causes, and treatments for dry mouth, along with tips for managing it and knowing when to see a professional.

Xerostomia vs. Salivary Hypofunction

Dry mouth is often discussed alongside salivary hypofunction, which means a measurable reduction in saliva flow, while xerostomia refers to the patient's subjective feeling of dryness. In practice, the two often overlap, but they aren't identical. A person can feel dry mouth even when saliva flow is only mildly reduced, and some people have low salivary flow without a strong sensation of dryness.

Term	Meaning	How It's Identified
Xerostomia	The sensation of a dry mouth	Reported by the patient
Salivary hypofunction	Reduced saliva production or flow	Measured clinically
Hyposalivation	Another term for low salivary flow	Measured clinically

What Saliva Does

Saliva does more than keep the mouth moist. It helps lubricate food for swallowing, supports taste and speech, buffers acids, protects teeth from decay, and helps maintain the health of oral tissues. When saliva production drops or doesn't function well, the mouth can feel dry, sticky, or sore, which is why dry mouth can affect eating, speaking, and oral health all at once.

Symptoms of Dry Mouth

Dry mouth symptoms vary from person to person, but the underlying cause is the same: not enough saliva to keep the mouth comfortably moist and functioning normally.

Mouth Dryness Sensation

Dry mouth is often a telltale sign that something is going on in the body, resulting in reduced saliva production. Inadequate saliva makes it harder to perform normal functions like speaking and eating.

Difficulty Chewing or Talking

Saliva helps lubricate the oral cavity, which aids your ability to speak and swallow the foods you enjoy. It's also necessary to avoid damaging your oral tissues.

A Burning Sensation

A burning sensation from dry mouth can be painful. It can be apparent on the tongue, lips, roof of the mouth, or other areas within the mouth and throat.

Altered Sense of Taste

A reduced sense of taste is common because saliva helps dissolve food molecules, allowing taste buds to detect them properly. Many people with dry mouth find they can't taste things as well.

Denture-Related Issues

A lack of saliva can cause problems for people wearing dentures, including trouble keeping dentures in place, oral sores, and oral infection.

Dryness in the Nose

Dryness within the sinuses can occur alongside dry mouth, which can be uncomfortable and may also trigger nosebleeds and trouble breathing.

Throat Soreness

Dry mouth can lead to a sore throat due to insufficient saliva production, making chewing and swallowing difficult and uncomfortable.

Split Lips

Lips can become dry due to dry mouth, leading to sores and cracked skin.

Thickened Saliva

A common symptom of dry mouth is stringy or thickened saliva. Increasing fluid intake can help thin saliva and ease this discomfort.

Increased Thirst

Increased thirst is often a sign of dehydration. Staying hydrated with water helps your body produce the saliva it needs for daily function.

A Dehydrated Tongue

Dry mouth can also make the tongue feel dry, swollen, and irritated, a common sign that saliva production isn't keeping up.

Mouth Sores

Oral sores can be caused by decreased saliva production, since saliva helps keep the mouth lubricated and contains minerals that protect against oral lesions.

Oral Infections

Because saliva helps buffer acids and support the mouth's natural defenses, less saliva can raise the risk of cavities and oral irritation over time. Saliva neutralizes harmful acids produced by oral bacteria and helps remineralize tooth enamel, making it stronger.

Bad Breath

An accumulation of bacteria often causes bad breath, or halitosis. Without adequate saliva, bacteria and food remnants tend to stick to teeth and in the mouth, causing a smelly odor.

Causes of Dry Mouth

Dry mouth has many possible causes, but medications are among the most common. The underlying issue may be reduced saliva flow, a change in saliva quality, or both.

Medications

Certain medications are known to cause dry mouth as a side effect, including those used to treat depression, anxiety, allergies, high blood pressure, and asthma. It's important to tell your dental professional about your medical history and current medications.

Polypharmacy, taking multiple medications at the same time, increases the risk of dry mouth, especially in older adults, since several medication classes can reduce saliva flow at once.

Salivary Gland Removal

Removing one salivary gland typically doesn't cause dry mouth, since the remaining glands can usually produce adequate saliva. Radiation therapy, on the other hand, often does cause dry mouth, which can raise your risk of cavities and mouth infections.

Breathing or Snoring Issues

Trouble breathing and snoring can leave your mouth open for extended periods, causing saliva to evaporate and leading to dry mouth and a sore throat.

Injury or Surgery

Traumatic injury or surgical procedures can damage the salivary glands and affect saliva production.

Physical Activity

Exercise can cause fluid loss from the body, contributing to dry mouth, so it's important to stay hydrated during physical activity.

Stress or Anxiety

Stress and anxiety can trigger hormonal changes that affect saliva production. Increased cortisol, for example, can impact saliva composition and contribute to dryness.

Diabetes

Research has reported a potential link between uncontrolled diabetes and dry mouth. Persistent dry mouth can increase the risk of infection, which could, in turn, worsen other conditions such as diabetes.

Dehydration

When you're dehydrated, your body doesn't have enough fluid to function properly, and reduced saliva production is one of the results.

Cancer Treatment

Cancer treatment, including radiation therapy and certain medications, can trigger dry mouth. Radiation may temporarily or permanently damage the salivary glands, directly affecting saliva production. Head and neck radiation is a well-established cause because salivary glands sit within the treatment field and can be permanently affected, which is why radiation-related dry mouth can raise the risk of decay and infection.

Nerve Damage

Damaged nerves following an injury or surgical procedure can result in dry mouth.

Other Medical Conditions

Other important medical causes include Sjögren's syndrome, HIV/AIDS, and dehydration-related illnesses. Dry mouth can also occur when saliva production drops because of autoimmune disease or as a side effect of treatment, not just from thirst or mouth breathing.

Smoking and Drinking

Tobacco and marijuana use, as well as alcohol use, can limit saliva production as a side effect.

If dry mouth is new, persistent, or tied to a medication change, it's worth asking a clinician or pharmacist for a medication review, since many cases improve when the dose, timing, or drug class is adjusted under medical supervision.

Treatments for Dry Mouth

Changing Medications

Your doctor may recommend adjusting your medications to help reduce dry mouth. Don't make changes to your medications without consulting a medical professional first. Many cases improve once the dose, timing, or drug class is adjusted under supervision.

Boosting Saliva Secretion

A doctor may prescribe medications to stimulate saliva production, such as pilocarpine (Salagen) or cevimeline (Evoxac). Other methods, like increasing water intake and chewing sugar-free gum, can also help stimulate saliva.

At-Home Relief Tips

Home care can reduce discomfort and make eating, speaking, and sleeping easier. The most helpful steps are to sip water regularly, use sugar-free gum or lozenges to stimulate saliva, and avoid alcohol-based mouthwash, tobacco, and very dry or salty foods.

Replacing Lost Secretion

Your dental professional may recommend saliva substitute products designed to mimic the lubricating properties of natural saliva.

Treating Tooth Decay

Dry mouth increases the risk of tooth decay, and left untreated, decay can lead to more serious health issues. Visit your dentist for treatment of both tooth decay and dry mouth.

Treating Infections

Visiting the dentist helps identify and treat oral infections before problems worsen, which can also help relieve dry mouth symptoms and improve your overall well-being.

Diagnostic Testing

If the cause of your dry mouth isn't clear, your dentist may recommend testing to evaluate your saliva production or salivary glands directly:

• Saliva flow test (sialometry): measures the rate of saliva flow to check for reduced production.
• Sialography: uses an X-ray with dye to evaluate the salivary glands and ducts for blockages or other issues.
• Tissue sample analysis (biopsy): examines a small sample of salivary gland tissue to help with diagnosis.

Preventing Dry Mouth

The best way to prevent dry mouth is to reduce triggers, especially medication side effects, dehydration, mouth breathing, smoking, and frequent sugary or acidic drinks. Prevention also depends on protecting saliva production and keeping the mouth moist enough for normal speech, swallowing, and eating.

• Limit sugary and acidic foods and drinks, which can increase your risk of dry mouth, tooth decay, and other problems, and can worsen existing symptoms.
• Chew sugar-free gum to help stimulate saliva production.
• Brush your teeth using a fluoride toothpaste.
• Rinse with an alcohol-free, fluoride-containing mouth rinse.
• Quit smoking to help improve your overall health.
• Visit your dentist at least twice a year for early detection and maintenance.
• Check with your doctor about whether dry mouth could be a side effect of any medications you're taking.
• Avoid mouth-breathing, which can dry out your mouth and increase your risk of cavities.
• Try using a humidifier to add moisture to the air.

When to See a Doctor

Persistent dry mouth should be evaluated if it lasts more than a few weeks, is severe, or is accompanied by trouble swallowing, mouth sores, frequent cavities, or a recent medication change.

Consulting with your dental professional is beneficial and necessary to maintain a healthy smile. If you're experiencing dry mouth, your dentist can help determine the right course of action, taking into account your medical and dental history. If needed, they may refer you to a medical professional, such as an ENT specialist, for further diagnosis and treatment.