Flurbiprofen axetil, an ester prodrug of flurbiprofen, undergoes premature hydrolysis in the gastrointestinal tract, causing mucosal injury and limiting its oral application. This study re-identified carboxylesterase 2 (CES2) as the primary enzyme responsible for this hydrolysis. Using glycyrrhetinic acid derivative GA13 as a selective CES2 inhibitor, we evaluated its effects on flurbiprofen pharmacokinetics, tissue distribution, efficacy and toxicity following oral co-administration with flurbiprofen axetil in rats. GA13 potently inhibited flurbiprofen axetil hydrolysis in human and rat intestinal microsomes (IC 50 = 1.8 μM and 4.8 μM, respectively) and moderately inhibited CYP2C9-mediated flurbiprofen metabolism in liver microsomes (IC 50 = 8.91 μM and 13.27 μM). Oral co-administration of GA13 (20 mg/kg) significantly improved flurbiprofen pharmacokinetics: C max and AUC increased by 60% and 85%, Tmax doubled, and t 1/2 prolonged by 30%. Tissue distribution studies revealed a 7-fold reduction of flurbiprofen in gastric tissue at 0.5 h, while distribution in other organs remained unchanged. In the carrageenan-induced paw edema model, combination therapy enhanced anti-inflammatory efficacy compared to flurbiprofen axetil alone. Importantly, 14-day repeated dosing showed that GA13 co-administration markedly attenuated gastrointestinal injury, preserved gastric PGE2 levels, and prevented weight loss. These benefits were attributed to CES2 inhibition-mediated reduction of local flurbiprofen generation. This study demonstrates that selective CES2 inhibition by GA13 enables effective oral delivery of flurbiprofen axetil with improved bioavailability, enhanced efficacy, and reduced gastrointestinal toxicity.