Cang Er Zi San — Xanthium Powder

On this page

1. Overview
2. TCM pattern
3. Key herbs
4. Formula actions
5. Conditions treated
6. Cautions

What is Cang Er Zi San?

Cang Er Zi San — Xanthium Powder — is a classical four-herb formula from Yan Yong-He’s Song dynasty Ji Sheng Fang (1253). It is one of the most widely prescribed formulas in Chinese herbal medicine for chronic sinusitis, allergic rhinitis and nasal congestion with Wind-Cold features. I see it used very frequently in the UK because the cold damp climate aggravates exactly the pattern it treats.

I prescribe Cang Er Zi San as part of bespoke herbal formulas from pharmaceutical-grade granules sourced from Sun Ten in Taiwan.

Cang Er Zi San TCM pattern

Prescribed for Wind invading the nose and sinuses: nasal congestion, copious clear or sticky white discharge, sneezing, loss of smell, frontal sinus pressure or headache, and a thin white tongue coat. Often exacerbated by cold or change of weather.

Key herbs

1. Cang Er Zi (Xanthium fruit) — chief herb; opens nasal passages and dispels Wind from the face
2. Xin Yi Hua (Magnolia flower) — opens nasal passages and dispels Wind-Cold
3. Bai Zhi (Angelica dahurica) — dispels Wind-Cold, opens nasal passages and relieves frontal pain
4. Bo He — clears Wind-Heat from the head and assists nasal opening

Formula actions

1. Dispels Wind and opens the nasal passages
2. Relieves frontal sinus headache
3. Resolves chronic nasal congestion

Conditions treated

1. Chronic sinusitis with thick white nasal discharge and frontal pressure
2. Allergic rhinitis and hay fever with congestion and sneezing
3. Nasal polyps with congestion (adjunctive)
4. Post-viral sinus congestion that lingers for weeks
5. Persistent loss of smell after a cold

Cautions

Cang Er Zi contains glycosides that are hepatotoxic at high doses or with prolonged use; modern Sun Ten granules use standardised, conservative doses, and the formula is best given in courses with breaks rather than continuously for many months. Contraindicated in pregnancy.

Always consult a qualified Chinese herbalist registered with the Register of Chinese Herbal Medicine (RCHM). Online herbal consultations are available.

Prefer to be treated from home? Chinese herbal medicine online consultations are available throughout the UK and worldwide.