A Review on Controlled Porosity Osmotic Drug Delivery Systems

Review Article

Abstract

Controlled porosity osmotic drug delivery systems (CPODS) represent a significant advancement in pharmaceutical technology, offering precise control over drug release rates through osmotic mechanisms. These systems utilize semipermeable membranes with controlled porosity to achieve sustained drug delivery, addressing limitations of conventional dosage forms. The fundamental principle involves water penetration through the semipermeable membrane, creating an osmotic gradient that facilitates drug release through formed micropores. CPODS demonstrate numerous advantages, including zero-order drug release kinetics, reduced dosing frequency, improved patient compliance, and minimized first-pass metabolism. The drug release is governed by various parameters such as osmotic pressure, membrane permeability, and pore characteristics, which can be optimized to achieve desired therapeutic outcomes. Recent developments have eliminated the need for mechanical drilling of delivery orifices, instead utilizing pore-forming agents that create micropores in situ. The system's effectiveness depends on critical components including osmotic agents, semipermeable membranes, pore-forming agents, and plasticizers. This innovative technology has shown particular promise in delivering both water-soluble and poorly soluble drugs, maintaining consistent plasma concentrations over extended periods. The robust in vitro-in vivo correlation and independence from physiological factors make CPODS an attractive platform for controlled drug delivery applications. As research continues, these systems show potential for expanding into novel applications such as pulsatile delivery and multi-drug therapy.