Causes and Risk Factors of Dry Mouth

Medicines, Chronic Diseases, Stress, and More

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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.

An adult male drinking a glass of water

elenaleonova / Getty Images

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.


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:

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

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:

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 

Persistent dry mouth can lead to serious problems with your teeth, gums, and mouth. If you have an unexplained dry mouth, consider speaking with a healthcare provider to find out why and what you can do to improve it.

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.


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

If you need help to quit smoking, speak with a healthcare provider, look into smoking cessation programs, or call 800-QUIT-NOW (800-784-8669).

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.


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.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Institute of Dental and Craniofacial Research. Dry mouth.

  2. Kapourani A, Kontogiannopoulos KN, Manioudaki AE, et al. A review on xerostomia and its various management strategies: the role of advanced polymeric materials in the treatment approaches. Polymers. 2022;14(5):850. doi:10.3390/polym14050850

  3. Mark AM. Is your mouth always dry? The Journal of the American Dental Association. 2020;151(12):972. doi:10.1016/j.adaj.2020.08.015

  4. Adolfsson A, Lenér F, Marklund B, Mossberg K, Çevik‐Aras H. Prevalence of dry mouth in adult patients in primary health care. Acta Odontologica Scandinavica. 2022;80(8):605-610. doi:10.1080/00016357.2022.2069282

  5. Thomson WM, Smith MB, Ferguson CA, Moses G. The challenge of medication-induced dry mouth in residential aged care. Pharmacy. 2021;9(4):162. doi:10.3390/pharmacy9040162

  6. American Dental Association. Xerostomia (dry mouth).

  7. Mortazavi H, Baharvand M, Movahhedian A, Mohammadi M, Khodadoustan A. Xerostomia due to systemic disease: a review of 20 conditions and mechanisms. Ann Med Health Sci Res. 2014;4(4):503-510. doi:10.4103/2141-9248.139284

  8. National Health Service U.K. Dry mouth.

  9. Mount Sinai. Dry mouth information.

  10. Saddu SC. Association of xerostomia and assessment of salivary flow using modified schirmer test among smokers and healthy individuals: a preliminutesary study. JCDR. doi:10.7860/JCDR/2014/6650.3846

  11. Le A, Palamar JJ. Oral health implications of increased cannabis use among older adults: Another public health concern? Journal of Substance Use. 2019;24(1):61-65. doi:10.1080/14659891.2018.1508518

By Ann Pietrangelo
Ann Pietrangelo is a freelance writer, health reporter, and author of two books about her personal health experiences.