Free Drug vs. Nanomedicine in Transdermal Patches: A Comparative Exploration of Etoricoxib Drug Release and Its Analgesic Activity

¹ Department of Basic Science and Humanities, Institute of Engineering and Management, Kolkata, India
² University of Engineering and Management, Kolkata, India
³ Regulatory affairs, Lupin Limited, Nagpur, India
⁴ Department of Pharmaceutical Technology, Jadavpur University, Kolkata, India
⁵ School of Materials Science and Nanotechnology, Jadavpur University, Kolkata, India
⁶ Department of Metallurgical and Material Engineering, Jadavpur University, Kolkata, India

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 29 May 2026

Abstract

Transdermal patches of traditional Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) such as diclofenac are already commercially available. Both diclofenac and etoricoxib (EB) are members of the NSAID family and are used as pain and inflammation relievers. However, transdermal formulations of EB, a non-traditional NSAID, have not yet been developed. The primary cause for the lack of such formulation might be the very poor aqueous solubility of EB. The traditional NSAIDs (non-selective COX inhibitor) raises the risk of renal damage, cardiovascular events and gastrointestinal side effects. EB is a selective COX-2 inhibitor and may have a lower risk of causing harm compared to traditional NSAIDs. Therefore, the transdermal patches of EB must be made highly desirable for patients requiring long-term pain management. This study presents the development of EB nanomedicine-impregnated transdermal patches to overcome its poor aqueous solubility and improve its therapeutic efficacy. The nanomedicines of EB were produced by encapsulating the drug into silica nanoparticles (SNPs) and sodium montmorillonite (Na-MMT) nanoclay, leveraging their high surface area, biocompatibility and ability to enhance solubility and skin permeation. The transdermal patches were fabricated incorporating the pure drug as well as nanomedicines to execute a comparative analysis between the patches with and without nanocarriers, performing various pharmaceutical experiments such as in vitro drug release study at pH 5. 5 and 7.4, skin irritation study on mice and rats, ex vivo skin permeation study using Franz diffusion cell, ex vivo drug release kinetics analysis and in vivo analgesic activity via Hot-Plate and Tail-Flick methods.