Dabigatran etexilate: a p-gp substrate. Using energy from adenosine triphosphate, p-gp receptors in the intestinal wall actively transport molecules across the epithelial monolayer. Because of its low bioavailability, dabigatran etexilate, with its moderate affinity for the p-gp receptor, is sensitive to the actions of p-gp efflux at the intestinal wall. Once absorbed into the intestinal bloodstream, dabigatran etexilate is hydrolysed by plasma esterases to its active principle, dabigatran. The latter is no longer a substrate for p-gp efflux.