Bilayer Tablets: Design, Technologies and Therapeutic Applications

Bilayer tablets are advanced oral solid dosage forms composed of two distinct layers, each formulated to achieve specific drug release profiles or to physically separate incompatible active pharmaceutical ingredients (APIs). These systems enable the combination of immediate-release (IR) and sustained-release (SR) components within a single unit, improving therapeutic efficacy, patient compliance, and pharmacokinetic control. This article reviews the principles, formulation strategies, manufacturing technologies, evaluation parameters, and recent advances in bilayer tablet systems, highlighting their growing importance in modern drug delivery.