Formulation and Evaluation of Chronomodulated Drug Delivery System

A pulsatile drug delivery system which is time dependent, consist of an effervescent core surrounded by consecutive layers of swelling and rupturable layers were prepared and evaluated. The cores comprising of the active agent Terbutaline sulphate (β₂ blocker) was prepared by direct compression method using different ratios of Microcrystalline cellulose, Osmotic agent and effervescent agent. The outer rupturable layer consists of Eudragit RS/RL (1:1) which surround the inner swelling layer comprising of Hydroxy propyl methyl cellulose E₅. The effect of various formulation and processing parameters were studied. The rupture and drug release studies were carried out using the USP paddle method at 50 rpm in 0.1 N HCl, and Phosphate buffer pH 6.8. The lag time of drug release was increased by increasing the rupturable layer and decreased by increasing the swelling layer level. The osmotic and the effervescent effect were involved in the drug release, as shown by the studies.