Causes and Risk Factors of Dry Mouth

Everyone gets dry mouth (xerostomia) on occasion. You might have that "cotton mouth" feeling when you're nervous, stressed out, or need a glass of water.

But persistent dry mouth is often a side effect of medication. Dry mouth can also be a symptom of diseases such as Sjögren's syndrome, diabetes, and human immunodeficiency virus (HIV) and AIDS. In addition, some lifestyle risk factors, such as smoking, are associated with dry mouth.

This article discusses some of the most common causes and risk factors for dry mouth.

Common Causes of Dry Mouth

Dry mouth is more common in women than in men. You're more likely to develop a dry mouth as you age, though it's not a normal part of aging.

Medications

Both over-the-counter (OTC) and prescription drugs can cause you to make less saliva than usual. The most common cause of dry mouth is taking multiple medications.

Hundreds of medications can cause dry mouth. The more of these medicines you take, the more likely you'll experience dry mouth. Taking numerous medications plus having certain health conditions can further increase the risk of dry mouth.

Dry mouth is most common among older people, who often take more medications than other age groups. The most common types of medicines to cause dry mouth are:

• Antidepressants (medication to treat depression)
• Antihistamines (medicines to relieve allergies)
• Antihypertensives (medicines to treat high blood pressure)
• Anti-seizure/antispasmodic drugs (medication to treat seizures)
  

Other medications that can lead to reduced saliva production and dry mouth include:

• Antipsychotics
• Benzodiazepines
• Anticholinergics
• Opioids
• Bronchodilators
  
• Skeletal and muscle relaxants
  
• Appetite suppressants
• Decongestants
• Migraine medications
  

If you suspect dry mouth is due to medication, don't stop taking it. First, speak with a healthcare provider and find out if there's another medication or alternative treatment.

Medical Treatment

Certain cancer therapies and other medical treatments can cause dry mouth.

Chemotherapy drugs can damage salivary glands. The effect is usually temporary, with symptoms beginning to improve when treatment ends.

Radiation therapy to the head and neck may cause permanent damage to salivary glands, which can cause long-term problems with dry mouth. So can radioactive iodine, which is used to treat some thyroid cancers.

Hematopoietic stem cell transplantation to treat specific blood and immune disorders can also cause dry mouth.

Chronic Diseases

Systemic, autoimmune, neurodegenerative, and other chronic conditions can cause dry mouth, with or without decreasing the amount of saliva. In some cases, dry mouth may be a symptom of:

• Sjögren's syndrome: A chronic autoimmune disease that causes joint pain, dry eyes and mouth, and digestive issues
• Diabetes: A group of conditions that impact the body's ability to control glucose
• Thyroid diseases: Hypothyroidism (underactive thyroid) and hyperthyroidism (overactive thyroid)
  
• Sarcoidosis: An inflammatory disease that affects the lymph nodes and lungs
• Parkinson's disease: A neurodegenerative disease causing tremors, stiffness, and speech issues
• Alzheimer's disease: A neurodegenerative disease that causes memory loss and confusion
• Depression and anxiety: Mental health disorders
• HIV/AIDS: A virus and disease that damages the immune system
• Hepatitis C: An infection that causes liver inflammation
• Epstein-Barr virus (EBV): A virus that can cause mononucleosis
• Rheumatoid arthritis (RA): An autoimmune disease that causes joint pain and swelling
• Systemic lupus erythematosus (SLE): An autoimmune disease that causes fatigue, butterfly rash, and joint pain
• Hemochromatosis: A genetic disorder that causes your body to absorb too much iron
• End-stage renal disease (ESRD): Kidney failure
• Scleroderma: An autoimmune disease that affects the skin and organs due to excess collagen production
  

Other Health Issues

Dry mouth can also occur with conditions such as:

• Dehydration
• Viral infections and other illnesses that cause fever
• Nutrient deficiencies
• Stress
  
• Nerve damage due to head or neck injury 

Lifestyle Risk Factors for Dry Mouth

Certain lifestyle factors may make you more likely to develop a dry mouth. Multiple lifestyle risk factors, medications, or chronic diseases can combine to increase the risk even more.

Diet

Your diet is probably not the main culprit in dry mouth. But you can exacerbate dry mouth when you consume foods and drinks such as:

• Caffeine (coffee, tea, and soft drinks)
• Sugary or fizzy soft drinks
• Alcohol, including mouthwashes that contain alcohol
• Acidic, spicy, or salty foods
• Dry, rough foods that irritate your tongue and mouth

Foods that can help with dry mouth include soft, bland foods with a high liquid content.

Smoking

Smoking tobacco significantly reduces saliva and increases dry mouth symptoms. Smoking marijuana is also associated with dry mouth.

Not Drinking Enough

Not getting enough fluids can dry your mouth, which may indicate dehydration. Be sure to drink plenty of water throughout the day, especially when you're physically active or out in hot weather.

Mouth Breathing

A dry mouth at night can happen when you sleep with your mouth open. You might do this when you're congested due to cold, flu, or allergies. Try to breathe through your nose rather than your mouth, and see a provider if you have concerns.

Summary

The most common cause of persistent dry mouth is medication. Hundreds of drugs can cause dry mouth; the more you take, the higher the risk. Dry mouth is also associated with chronic diseases such as Sjögren's syndrome and diabetes. There are a few lifestyle factors, such as smoking, that can make matters worse.

The chance of developing dry mouth increases with age, though it's not a natural part of aging. As you age, you're more likely to take multiple medications or have underlying health conditions that can cause dry mouth.