Xerostomia is common in the elderly and can be caused by which of the following?

• A. Medications
• B. Bacteria in the mouth
• C. Vitamin C deficiency
• D. Excess brushing

Answer: (A)

Xerostomia, or dry mouth, in older adults is most often caused by medications that reduce saliva production. Many drugs used with aging—such as antihistamines, antidepressants, antipsychotics, and diuretics—have drying effects or promote dehydration, leading to a consistently dry mouth. Saliva is essential for lubrication, digestion, and protecting teeth, so its reduction creates symptoms and increases dental risks. Bacteria in the mouth aren’t a primary cause of dryness; they may flourish when saliva is low, but dryness itself comes from the medications. Vitamin C deficiency affects gums and healing rather than salivary flow, and brushing more than usual doesn’t create dry mouth—though aggressive brushing can irritate tissues.