The polypharmacy-xerostomia-nutrition triad: the clinical framework for older adults

Polypharmacy, the concurrent use of five or more medications, affects the majority of community-dwelling older adults aged 65 and older in the United States. A clinically underrecognized consequence is medication-induced xerostomia and salivary hypofunction, which critically impair oral function, food selection, and nutritional status.

This mini-review synthesizes mechanistic and clinical evidence linking polypharmacy-induced xerostomia to nutritional decline in older adults and proposes a clinical framework for integrated dental-medical screening.

A narrative review of English-language peer-reviewed literature published between 2000 and 2025 was conducted using PubMed/MEDLINE, CINAHL, and Cochrane databases. Studies examining xerogenic medication burden, salivary function, masticatory performance, dietary intake, and nutritional biomarkers in adults aged 60 and older were included.

Xerogenic medications, including diuretics, antihypertensives, antidepressants, antihistamines, and anticholinergics, are highly prevalent in older adults and exert dose-dependent suppression of salivary flow via anticholinergic, aquaporin-disrupting, and sympatholytic mechanisms. Salivary hypofunction impairs bolus formation, swallowing efficiency, and gustatory function, driving avoidance of fibrous and nutrient-dense foods. This dietary shift is associated with protein-energy malnutrition, sarcopenia, and micronutrient deficiencies. Socioeconomic and structural disparities amplify nutritional risk among low-income and minority older adults.

The polypharmacy-xerostomia-nutrition triad represents a tractable but systematically under-addressed pathway to preventable malnutrition and functional decline. Interprofessional screening, patient-centered salivary management strategies, and expanded dental benefit coverage are urgently needed.