Formulation and evaluation of transdermal patches of meloxicam

The present study aimed to formulate and evaluate matrix-type transdermal patches of Meloxicam using the solvent casting method with ethyl cellulose (EC) and polyvinylpyrrolidone K-30 (PVP K-30) as rate-controlling polymers. The formulations were prepared using PEG 200 as a plasticizer, DMSO as a penetration enhancer, and triethanolamine to adjust pH to skin-compatible levels (6.5-7). Nine formulations (F1-F9) were developed by varying the ratio of EC and PVP K-30. The prepared patches were evaluated for physical characteristics, thickness, weight variation, drug content, folding endurance, surface pH, moisture uptake, moisture content, swelling index, in vitro drug release, release kinetics, and stability. All patches exhibited satisfactory physical properties with uniform thickness, weight and drug content. The folding endurance ranged from 115 to 128, indicating good mechanical strength. Surface pH (6.6-6.8) confirmed skin compatibility. Moisture uptake and moisture content were within acceptable limits, ensuring patch stability. Swelling studies revealed that patches with higher PVP K-30 content showed greater water absorption due to its hydrophilic nature, while EC imparted structural integrity. In vitro drug release studies indicated that increasing the content of hydrophobic EC retards the release, whereas the inclusion of hydrophilic PVP K30 enhances it. Batch F7 offered a balanced release profile and considered optimal for sustained transdermal delivery of meloxicam that folowes Korsmeyer-Peppas kinetics, indicating a non-Fickian diffusion mechanism. Stability studies demonstrated no significant changes in drug content or appearance over 3 months. The study concluded that meloxicam transdermal patches using an optimal blend of EC and PVP K-30 can provide controlled drug delivery with desirable physicochemical and mechanical properties, offering a promising alternative to oral administration.