Phellodendron bark (Huang Bai), a traditional Chinese medicinal herb, has been used historically for its anti-inflammatory and antimicrobial properties. In Traditional Chinese Medicine (TCM), it is commonly included in herbal formulas for conditions characterized by "damp-heat," which can include some skin and vascular inflammations. Phlebitis, or inflammation of a vein, is sometimes addressed in TCM using herbs like Phellodendron bark, although it is not a primary or highly specific remedy for this condition. The rationale is based on its traditional classification as an herb that clears heat and dampness, which could correspond to symptoms seen in phlebitis such as redness, swelling, and warmth. From a scientific perspective, there is some in vitro and animal evidence that Phellodendron bark constituents (notably berberine) have anti-inflammatory effects. However, there are no robust clinical trials or high-quality scientific studies specifically examining the efficacy of Phellodendron bark for the treatment or management of phlebitis in humans. Thus, its use for this purpose is based mainly on tradition rather than scientific validation. The overall evidence for its effectiveness in phlebitis is weak, and its use is not endorsed by modern medical guidelines.