Phellodendron Decoction

In a randomized, double-blind, placebo-controlled trial, 60 patients post-anal fistulotomy received daily topical ultrasonically atomized CPD (n=30) or placebo (n=30). Primary endpoints were healing time and scores for edema, pain, and exudation on days 3 and 7. Secondary outcomes included inflammatory cytokine levels, hydroxyproline, angiogenesis, and direct histological and ultrastructural assessment of NETs in granulation tissue. To dissect the underlying mechanism, we investigated the effect of CPD on NETosis in primary human neutrophils, measuring NET formation, reactive oxygen species (ROS) generation, and expression of key mediators (CitH3, PAD4).