In older adults, many prescription and OTC drugs cause which condition that increases caries risk?

• A. Dry mouth
• B. Increased saliva
• C. Tooth whitening
• D. Gum overgrowth

Answer: (A)

Dry mouth, or xerostomia, is the condition described. In older adults, many prescription and OTC drugs reduce salivary flow, leaving the mouth dry. Saliva protects teeth by washing away sugars and food particles, buffering acids produced by bacteria, and supplying minerals for remineralization. When saliva decreases, acids linger longer, plaque can accumulate more easily, and root surfaces (which are more exposed in aging) are especially vulnerable to decay. This combination raises caries risk significantly in seniors on multiple medications. Increased saliva would actually lower risk, tooth whitening is cosmetic and not a caries driver, and gum overgrowth is a different drug effect that doesn’t inherently increase caries risk the way dry mouth does.