An In-Depth Look at Dry Mouth (Xerostomia)

Dry mouth, also known as xerostomia, occurs when the salivary glands do not produce enough saliva, or when the quality of saliva is reduced. Saliva plays a critical role in oral health, digestion, and comfort, and reduced salivary flow can significantly affect both dental health and quality of life.

What Does Saliva Do?

Although saliva is largely water, it contains enzymes, proteins, and minerals that serve several important functions:

• Helps break down food and begin digestion
• Washes away bacteria and food debris
• Protects teeth against decay
• Maintains oral tissue health
• Supports taste and speech
• Lubricates food to aid chewing and swallowing

When saliva production decreases, these protective functions are compromised.

Symptoms of Dry Mouth

Dry mouth symptoms can vary in severity and may include:

• Persistent dryness or sticky feeling in the mouth
• Thick or stringy saliva
• Difficulty speaking, chewing, or swallowing
• Changes or loss of taste
• Problems wearing dentures
• Increased tooth decay
• Bad breath

Because saliva helps neutralize acids and control bacterial growth, chronic dry mouth significantly increases the risk of cavities and oral infections.

What Causes Dry Mouth?

Dry mouth can develop for several reasons, often involving more than one contributing factor.

Medications

The most common cause of dry mouth is medication use. Many prescription and over-the-counter drugs list dry mouth as a side effect. The risk increases as the number of medications increases.

Medications commonly associated with dry mouth include those used to treat:
• Depression and anxiety
• ADHD
• High blood pressure
• High cholesterol
• Allergies (antihistamines)

Aging

Aging itself does not directly cause dry mouth. However, as people age, they are more likely to take multiple medications, which increases the likelihood of xerostomia.

Cancer Treatment

Chemotherapy can temporarily alter salivary flow or composition, with saliva often returning after treatment ends. Radiation therapy to the head and neck can cause permanent damage to the salivary glands, leading to long-term or irreversible dry mouth.

Medical Conditions

Certain health conditions can impair salivary function. These include autoimmune diseases such as Sjögren’s syndrome. Chronic mouth breathing, snoring, and sleep apnea can also contribute to oral dryness.

Methamphetamine Use

Methamphetamine use can cause severe dry mouth and rapid tooth destruction, commonly referred to as “meth mouth.” This combination of reduced saliva, acidic environment, and poor oral hygiene can lead to extensive dental damage.

Treating Dry Mouth

While there is no universal cure for dry mouth, many strategies can help manage symptoms and reduce complications.

Over-the-counter options include artificial saliva products, rinses, sprays, and moisturizing gels designed to relieve dryness. Toothpastes and mouthwashes formulated for dry mouth can also improve comfort and reduce irritation.

Prescription medications may be appropriate in certain cases. Drugs such as pilocarpine (Salagen) or cevimeline (Evoxac) can stimulate natural saliva production and are often used in patients with conditions such as Sjögren’s syndrome.

Patients often find the most relief by combining multiple approaches, including:
• Using a moisturizing gel before bedtime
• Sucking on sugar-free lozenges to stimulate saliva
• Staying well hydrated throughout the day

Protecting Your Teeth When You Have Dry Mouth

One of the most serious complications of dry mouth is an increased risk of tooth decay. Without adequate saliva, teeth are more vulnerable to acid attack and bacterial damage.

Preventive strategies include:
• Using prescription-strength fluoride toothpaste
• Maintaining meticulous oral hygiene
• Scheduling regular dental evaluations

These measures can significantly reduce the risk of cavities and costly dental treatment.

When to Seek Evaluation

If you experience persistent dry mouth or worsening oral symptoms, professional evaluation is important. Identifying the underlying cause allows for targeted treatment and helps protect long-term oral health.

Reviewed and updated January 2026