Formulation and Evaluation of Herbal Transdermal Patch of Clerodendrum Infortunatum for Anti-Inflammatory Activity

Transdermal drug delivery systems (TDDS) represent a modern approach for delivering therapeutic agents through the skin into the systemic circulation, offering significant advantages including avoidance of first-pass metabolism, controlled drug release, improved bioavailability, and enhanced patient compliance. Clerodendrum infortunatum Linn. (Family: Lamiaceae), commonly known as Bhat or Bhant, is a well-known medicinal plant with significant anti-inflammatory, antibacterial, antifungal, and wound-healing properties. Its active phytoconstituents — including flavonoids, terpenoids, alkaloids, and steroids — make it a potential candidate for topical and transdermal applications, particularly for skin disorders such as eczema, dermatitis, and inflammatory conditions. The present study aimed to formulate and evaluate transdermal herbal patches of C. infortunatum leaf extract by solvent casting technique using polymers HPMC and PVA. Three formulations (F1, F2, F3) were developed with varying drug concentrations. The patches were evaluated for physical appearance, thickness, weight uniformity, folding endurance, moisture content, moisture uptake, flatness, drug content uniformity, in vitro drug permeation using Franz diffusion cell, skin irritation test, and stability studies. Phytochemical screening confirmed the presence of flavonoids, alkaloids, tannins, steroids, and phenolic compounds. Formulation F2 (HPMC:PVA = 2:3) exhibited the best overall performance, with drug content of 97.8%, folding endurance of 225, and cumulative drug permeation of 91.2% in 8 hours following Higuchi diffusion kinetics. Skin irritation studies confirmed the patches were non-irritant. Stability studies showed no significant changes at room temperature over 4 weeks.