Si Miao San — Four Marvels Powder

On this page

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

What is Si Miao San?

Si Miao San (“Four Marvels Powder”) is the principal Chinese formula for Damp-Heat in the lower jiao. It is the expansion of Er Miao San (Cang Zhu and Huang Bai) by adding Yi Yi Ren and Niu Xi, creating a balanced formula that clears Damp-Heat while strengthening the Spleen and directing the action to the lower body. The formula is widely used in modern practice for gout, rheumatoid arthritis, prostatitis, urinary tract infections and chronic leucorrhoea.

Si Miao San TCM pattern

Prescribed for Damp-Heat pouring downward to the lower jiao, characterised by: red, swollen, hot, painful lower limbs or joints, heaviness and weakness of the legs, yellow turbid urine, yellow malodorous leucorrhoea, perineal itching, a yellow greasy tongue coat, and a soggy rapid pulse. The pattern represents Damp-Heat that has settled in the lower body, distinct from generalised Damp-Heat patterns.

Key herbs

1. Huang Bai (Phellodendron bark) — the chief herb; drains Damp-Heat from the lower jiao
2. Cang Zhu (Atractylodes lancea) — dries Damp and strengthens the Spleen
3. Yi Yi Ren (Job’s tears) — drains Damp via urination; strengthens Spleen
4. Niu Xi (Achyranthes root) — directs herbs downward and tonifies Liver and Kidney

Formula actions

1. Clears Damp-Heat from the lower jiao
2. Strengthens the Spleen
3. Directs the action downward to the legs and pelvis

Conditions treated

1. Gout — substantial modern evidence base; reduces serum uric acid and acute flares
2. Rheumatoid arthritis with hot swollen joints
3. Damp-Heat leucorrhoea and pelvic inflammatory disease
4. Chronic prostatitis and urinary tract infections
5. Eczema and weeping skin disorders of the lower body
6. Diabetic foot complications with Damp-Heat
7. Atrophy disorders of the lower limbs from Damp-Heat

Cautions

Contraindicated in cold patterns and Yin deficiency without Damp-Heat. Use cautiously in Spleen Yang deficiency. Always consult a qualified Chinese herbalist registered with the RCHM. Online herbal consultations are available.