FORMULATION STRATEGIES & CHALLENGES IN PULMONRY DRUG DELIVERY

Abstract

Pulmonary drug delivery systems (PDDS) have emerged as an effective and non-invasive approach for both local and systemic drug administration, owing to the unique anatomical and physiological features of the lungs. The large alveolar surface area, thin epithelial barrier, rich vasculature, and avoidance of hepatic first-pass metabolism enable rapid onset of action, improved bioavailability, and reduced systemic side effects. Advances in particle engineering technologies—such as micronization, spray freeze-drying, and supercritical fluid techniques—have enabled the production of reparable particles with enhanced deposition in the deep lung regions. However, challenges including mucociliary clearance, enzymatic degradation, limited drug stability, and patient-dependent device handling remain critical barriers. Overall, the collective findings emphasize that continued innovations in formulation design, delivery devices, and targeting strategies are essential to fully realize the therapeutic potential of pulmonary drug delivery systems in modern drug therapy.