Urolithiasis, or kidney stone disease, poses a persistent global health concern due to its high recurrence rate and the financial burden of conventional treatments. This study explored the synergistic in vitro anti-lithiatic potential of solid-phase extraction (SPE) concentrates derived from banana (Musa spp.), mango (Mangifera indica), and camansi (Artocarpus camansi) fruit peels. The extracts were assessed for their ability to inhibit calcium oxalate nucleation and aggregation using UV-Vis spectrophotometry at 620 nm. Following collection, the fruit peels underwent ethanol maceration, rotary evaporation, and SPE purification. Treatments—prepared individually and in combinations at 100 µg/mL—were tested against calcium oxalate crystal formation. Results showed that the polyfruit blend demonstrated significantly greater inhibition of nucleation (58.63%) and aggregation (63.07%) compared to individual extracts, second only to potassium citrate as the positive control. Quantitative phytochemical analysis confirmed the presence of saponins, flavonoids, and tannins, contributing to the observed bioactivity. ANOVA and Scheffé post hoc tests validated significant differences (p < 0.01) among treatment groups. This research bridges traditional pharmacognosy and modern biotechnology, offering an opportunity to develop health tourism products from agricultural waste. It catalyzes interdisciplinary collaborations among pharmacists, medical practitioners, tourism professionals, and farmers—showcasing how locally sourced bioactive compounds can shape a sustainable and health-oriented tourism economy while uplifting rural agricultural sectors. The study highlights the therapeutic and economic potential of fruit peel waste in preventive nephrology and recommends further in vivo and formulation studies for clinical translation and commercialization.