Bilastine (BL) is a novel non-sedating second-generation antihistamine, and its bioavailability is about 60%. Objective: To compare the bioavailability of prepared oral self-nanoemulsions of BL (BL-SNE) with that of pure BL and marketed tablets. Methods: Four groups of Wistar rats were used in this study, each with six rats weighing between 200 and 250 g. They were treated orally using a a gavage tube. The groups were fed either with conventional tablets ("Alerbix®") after being ground and dispersed with deionized water (DIW), treated with BL-SNE or fed with pure BL powder suspension. The fourth group did not receive any medication. The concentration of BL in the rat’s plasma was measured using HPLC. We used Trandolapril as an an internal standard. Results: The bioavailability results for the the prepared formula, tablet, and pure BL were 24289.91 ng/ml, 0.75 h, 12.81, 97844.7 ng.h/ml, and 98732.9 ng/ml, respectively, for the BL-SNE formula, and 15840.37, 1.0, 13.014, 66140.4, and 67088.3 for the tablets. Meanwhile, the BL suspension demonstrates 10830.12, 1.0 h, 12.96, 59397.12 ng/ml, and 60534.64 ng/ml, respectively. Conclusions: The relative bioavailability of BL-SNE was 1.47 and 1.6 times higher than that of marketed tablets and pure BL, respectively. This indicates an improvement in BL's bioavailability.
