The effect of sparkling water on the systemic pharmacokinetics of paracetamol in older adults

Paracetamol absorption kinetics show considerable variability in older adults, complicating the development of effective dosing regimens in the advanced-age population. In previous research, sparkling water has been shown to influence absorption-related processes. This study aimed to apply these findings to older adults and investigate the impact of sparkling water on absorption-related variability and early exposure. To this end, fourteen volunteers, with a median age of 72.5, were enrolled in a small-scale, randomised, controlled clinical trial with a cross-over design. A single immediate-release 500 mg paracetamol tablet was administered with sparkling or still water. Venous blood samples were collected regularly over 8 hours and analysed using HPLC-UV. Reduced variability of absorption-related parameters and a trend towards higher early exposure were observed in the sparkling water group, as demonstrated by a 1.6-fold increased AUC0-30min, a 2-fold reduced geometric coefficient of variation (GCV) for AUC0-30min, and a reduced median [interquartile range] Tmax of 25.0 [20.0-30.0] min compared to 30.0 [25.0-45.0] min. Based on our findings, sparkling water as a real-life dosing condition might improve paracetamol absorption kinetics and early exposure in the advanced-age population.