Densefruit Pittany Root Bark

Chinese
白鲜皮
Pinyin
Bai Xian Pi
Latin
Cortex Dictamni

TCM Properties

Taste
bitter, acrid
Temperature
cold
Channels
Liver, Gallbladder, Spleen, Stomach, Lung

Traditional Use

Primary Actions

  • Clears heat and dries dampness from the skin - Bai Xian Pi is a classic choice for eczema, damp sores, weeping lesions, and red itchy eruptions with a clear damp-heat component.
  • Dispels wind and relieves itching - traditional use extends to urticaria, pruritus, and recurrent flare-type skin disorders when itching is driven by heat and dampness rather than simple dryness.
  • Resolves toxicity and eases damp-heat obstruction - beyond dermatology, the herb is used for damp-heat arthralgia, jaundice, and lower-body irritative conditions when heat and toxin need to be cleared.

Secondary Actions

  • Bai Xian Pi is frequently used both internally and externally, which reflects how strongly the herb is associated with weeping, inflamed, or itchy skin presentations.
  • Its traditional character is clearing and drying rather than nourishing, so it is better suited to robust damp-heat patterns than to dry, deficient, or cold constitutions.

Classic Formulas

  • Xiao Feng San modifications - common modern-traditional pairing when wind, dampness, and itching coexist in eczema or urticaria patterns.
  • Bai Xian Pi with Ku Shen and Di Fu Zi - classic skin-focused combination logic for damp-heat itching and fungal-type lesions.
  • Dermatitis and damp-heat sore formulas with Huang Bai or Long Dan Cao - pattern-based combinations when heat and toxin are more intense.

Classical References

  • TCM Wiki describes Bai Xian Pi as bitter, slightly pungent, and cold, entering the Liver, Gallbladder, Spleen, Stomach, and Lung channels, with actions of clearing heat, drying dampness, removing toxicity, and dispelling wind.
  • Traditional use strongly centers on eczema, itchy skin disease, vulvar itching, damp-heat sores, and damp-heat arthralgia.

Modern Research

Active Compounds

  • Quinoline alkaloids including dictamnine - characteristic constituents heavily discussed in both pharmacology and hepatotoxicity literature
  • Limonoids and protolimonoids - major secondary metabolites investigated for anti-inflammatory and skin-related activity
  • Phenylpropanoids and glycosides - additional compounds contributing to broader phytochemical complexity

Studied Effects

  • A 2021 review summarized the traditional uses, phytochemistry, pharmacology, and toxicology of Dictamnus dasycarpus, noting anti-inflammatory, cardiovascular, liver-related, and anticancer research directions while also highlighting real safety concerns (PMID 34874447).
  • Mouse research on the root bark found anti-inflammatory activity in allergic contact dermatitis, aligning closely with the longstanding traditional use of Bai Xian Pi for eczema, itching, and urticarial skin disease (PMID 23850712).
  • Newer work continues to support skin-barrier and dermatitis-related benefits in animal models, but hepatotoxicity investigations also warn that safety cannot be treated casually (PMID 39684888; PMID 37446707).

PubMed References

Safety & Interactions

Contraindications

  • Spleen-Stomach deficiency cold
  • Dry deficient skin patterns without damp-heat
  • Prior herb-induced liver injury or unexplained active liver disease without close supervision

Cautions

  • Although Bai Xian Pi has a strong traditional skin reputation, modern literature also includes hepatotoxicity signals for Dictamnus dasycarpus and its alkaloid-rich fractions.
  • Internal use should be more cautious with concentrated extracts than with ordinary decoction-level traditional use.
  • Patients using multiple potentially hepatotoxic herbs or medications deserve extra monitoring.

Conditions