How can medications affect dental caries risk?

• A. Cause dry mouth, increasing risk
• B. Increase saliva
• C. Strengthen enamel
• D. No effect

Answer: (A)

Medications influence dental caries risk mainly through their effect on saliva. Saliva protects teeth by washing away sugars, buffering acids, and providing minerals for remineralization; when a drug causes dry mouth, these protective actions are reduced, allowing sugars to remain longer, acids to buildup, and enamel to demineralize more easily. This dry-mouth (xerostomia) effect raises caries risk, especially with long-term use or at night. Some medicines may also contain sugar or acidic formulations that further promote decay, but the primary issue is reduced saliva. Options suggesting increased saliva, enamel strengthening, or no effect would not raise caries risk.