Cang Fu Dao Tan Tang — Phlegm-Damp PCOS Formula

On this page

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

What is Cang Fu Dao Tan Tang?

Cang Fu Dao Tan Tang is the classical Chinese herbal formula for Phlegm-Damp obstructing the uterus — the dominant TCM pattern underlying polycystic ovary syndrome (PCOS) in overweight or insulin-resistant women. Derived from Er Chen Tang as the base, with Cang Zhu and Xiang Fu added to address the gynaecological dimension, the formula resolves Phlegm-Damp, regulates Qi and unblocks the channels of the lower abdomen. Modern research demonstrates effects on ovulation rate, menstrual regularity and insulin sensitivity in PCOS populations.

Cang Fu Dao Tan Tang TCM pattern

Prescribed for Phlegm-Damp obstructing the uterus with Liver Qi stagnation, characterised by: anovulation or irregular ovulation, scanty or absent periods, weight gain particularly around the middle, oily skin and acne, hirsutism, a soft doughy quality to the body, white vaginal discharge, a swollen tongue with thick white coat and tooth-marked edges, and a slippery or wiry pulse. This is the pattern most commonly seen in PCOS with weight, insulin resistance and ovulatory disorder.

Key herbs

1. Cang Zhu (Atractylodes lancea) — dries Damp and strengthens Spleen
2. Xiang Fu (Cyperus rotundus) — the gynaecological Qi-regulator; spreads Liver Qi and regulates the menses
3. Chen Pi (tangerine peel) — regulates Qi and dries Damp
4. Ban Xia (pinellia rhizome) — transforms Phlegm
5. Fu Ling (poria) — leaches Damp and calms the Shen
6. Dan Shen (salvia) — invigorates Blood (commonly added in modern PCOS practice)
7. Zhi Ke — regulates Qi
8. Gan Cao — harmonises

Formula actions

1. Dries Damp and transforms Phlegm
2. Regulates Qi and spreads the Liver
3. Unblocks the uterus and channels of the lower jiao
4. Restores ovulation and menstrual regularity

Conditions treated

1. Polycystic ovary syndrome (PCOS) — particularly with weight and Phlegm-Damp features
2. Anovulation and oligo-ovulation from Phlegm-Damp
3. Amenorrhoea with weight gain
4. Weight gain with PCOS pattern
5. Infertility from Phlegm-Damp obstructing the uterus
6. Insulin resistance with menstrual irregularity
7. Hirsutism and acne with PCOS pattern

Cautions

Not used in Yin deficiency or true Heat patterns without modification. The drying nature of the formula is inappropriate for thin, dry, hot patients — PCOS in slim, lean women usually requires a different pattern approach. Avoid in pregnancy. Always consult a qualified Chinese herbalist registered with the Register of Chinese Herbal Medicine (RCHM). Online herbal consultations are available. See the prices page for costs.