Formulation and Evaluation of Transdermal Polyherbal Patch for the Management of Rheumatoid Arthritis

Abstract

Objective: To design, develop, and evaluate a transdermal polyherbal patch incorporating standardized extracts of Boswellia serrata, Curcuma longa, Zingiber officinale, and Piper nigrum for sustained anti‑inflammatory action relevant to rheumatoid arthritis (RA). Methods: Solvent‑casting films composed of HPMC/PVP/EC with PEG‑400 and permeation enhancers (oleic acid, DMSO, limonene) were optimized by physicomechanical and biopharmaceutical criteria. Comprehensive quality attributes—thickness, weight uniformity, folding endurance, moisture handling, swelling index, tensile strength, drug content, and WVTR—were quantified. In‑vitro release, ex‑vivo porcine skin permeation (lag time, flux, permeability coefficient), and a protein‑denaturation inhibition assay were conducted. Accelerated stability (40°C/75%RH, 3 months) was assessed for the lead batch. Results: Batches F2–F4 met predefined quality targets; F3 exhibited balanced mechanics (tensile strength 33±2 MPa; elongation 32±4%) and sustained release (>75% at 12 h; ~95% at 24 h) with the highest steady‑state flux (28.9 µg/cm²/h). Anti‑inflammatory potential of polyherbal films approached a standard diclofenac gel in the in‑vitro model. Stability of F3 indicated minimal loss of drug content (−1.1% over 3 months) and preserved release. Conclusion: The polyherbal transdermal patch demonstrates robust manufacturability, sustained release, efficient skin transport, and promising anti‑inflammatory activity, supporting its potential as an adjunct modality for RA symptom management.