bilastine + ketoconazole

Bilastine + ketoconazole refers to the concomitant use of two pharmaceutical agents with distinct mechanisms of action. Bilastine is a second-generation, non-sedating antihistamine that acts as a selective antagonist at the histamine H1 receptor, used primarily for the symptomatic treatment of allergic rhinitis and urticaria. Ketoconazole is an imidazole antifungal agent that inhibits fungal ergosterol synthesis by blocking cytochrome P450-dependent 14α-demethylase, and is used to treat various fungal infections when other treatments are unsuitable. When administered together, ketoconazole significantly increases plasma concentrations of bilastine due to inhibition of intestinal efflux transporters (notably P-glycoprotein), leading to increased risk of QT interval prolongation on ECG—a clinically relevant drug-drug interaction[2][5]. This combination does not represent a fixed-dose product but rather describes co-administration for clinical or pharmacological study purposes.