Vol. 7, Issue 2, Part C (2025)

In recent years, pulsatile drug release systems (PDRS) have emerged as an advanced alternative to conventional drug delivery methods. Unlike continuous-release formulations, PDRS are designed to deliver drugs rapidly after a predetermined lag time, making them particularly advantageous for chronotherapy, targeted therapy, and drugs prone to degradation or side effects during sustained exposure.

PDRS can be broadly classified into single-pulse systems and multi-pulse systems. Typically, these formulations consist of a drug-containing core, an intermediate swelling layer, and an outer coating composed of an insoluble material combined with a semipermeable polymer. The lag time before drug release is influenced by several factors, including the permeability and mechanical strength of the outer coating as well as the swelling and rupture characteristics of the intermediate layer.