Gan Sui甘遂
Kansui Radix · Kansui Root
Overview
The most drastic of the harsh water-expelling purgatives: the tuberous root of a spurge, bitter and cold and frankly toxic. It drives accumulated fluid out of the chest, abdomen and limbs through violent watery stools, and disperses swellings when applied externally. Modern practice uses it only vinegar-processed, only in pills and powders, only briefly, and only where a confirmed fluid excess in a robust patient makes the risk defensible.
Nature & Flavor
Bitter · Cold · ToxicChannels
Lung · Kidney · Large IntestineTypical Dosage
0.5–1 gActions
3 core actions
- Drives out water and thin mucusSevere generalized edema, abdominal fluid distension, and fluid congesting the chest and flanks — the water leaves rapidly through the stool.
- Reduces swelling, disperses nodulesPowdered and applied externally to sores, swellings and stubborn lumps.
- Vinegar processing is not optionalThe raw root is far more irritant. Internal use is always of the vinegar-processed drug, and even then in pills or powder rather than decoction — the active diterpenes are poorly extracted into water, which makes a decoction both weaker and unpredictable.
In Formulas
Formulas containing Gan Sui
Indications & Clinical Uses
- Severe generalized edema and abdominal fluid accumulation, in a patient strong enough to be purged
- Fluid congestion of the chest and flanks with fullness and pain
- Phlegm-fluid obstruction with wheezing, classically in pill form
- Externally, on swellings and stubborn nodules
Western Medical Keywords
Searchable condition terms
Contraindications
Cautions
Toxic, and among the harshest drugs in the materia medica. Its diterpene esters are violently irritant to the gut: too much brings severe abdominal pain, vomiting, profuse watery diarrhea, dehydration and electrolyte loss, and in serious poisoning circulatory collapse. The pharmacopoeia ceiling is 1.5 g per day, of the vinegar-processed root, taken in pills or powder; raw Gan Sui is for external use only. Classical incompatibility: it is never combined with Gan Cao 甘草 — and because Gan Cao appears in a great many prescriptions, the whole formula has to be checked, not just the pair. Contraindicated in weak, elderly, deficient or already dehydrated patients. Never a self-medication herb, under any circumstances.
Contraindicated in pregnancy: Absolutely contraindicated in pregnancy — it can bring on miscarriage; avoid while breastfeeding as well
For licensed practitioners’ reference only
References
- Shen Nong Ben Cao Jing《神农本草经》(classical source, public domain).
2. Bensky, Clavey & Stöger. Chinese Herbal Medicine: Materia Medica, 3rd ed.
3. 《中华人民共和国药典》.
Professional reference notice. Entries are scholarly references for licensed TCM practitioners and students — not medical advice, and not a recommendation to self-prescribe. Chinese herbal formulas should be used under the guidance of a qualified practitioner. Content is an original editorial compilation by Cura x Cura, cross-checked against the cited references.