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Cura x Cura

Mang Xiao芒硝

Natrii Sulfas · Mirabilite · Glauber's Salt

Downward-Draining Herbs 泻下药《名医别录》

Overview

A refined mineral — crystallised sodium sulfate, worked up from raw mirabilite and recrystallised until it runs clear. Salty, bitter and cold, it does to hardened stool what water does to baked ground: it softens. In the heat-accumulation patterns of the Yangming it is paired with Da Huang so that dry impacted stool, which purging alone will not shift, is loosened before it is driven out. It is never boiled with the other herbs — the finished decoction is strained and poured over it so that it dissolves.

Nature & Flavor

Salty, bitter · Cold

Channels

Stomach · Large Intestine

Typical Dosage

10–15 g
芒硝Photography for this entry is on its way.

Actions

3 core actions

  • Purges accumulation, softens hardnessDry hard stool that will not pass, with abdominal fullness, pain and fever; classically combined with Da Huang so that the dryness and the heat are removed together.
  • Clears heat, reduces swellingMouth and tongue sores, swollen painful throat, red hot skin swellings — most often as a rinse or a compress rather than swallowed.
  • External use on an engorged breastDissolved in water and applied over a hot, distended, painful breast; the same application is used when milk supply is deliberately being reduced.

In Formulas

Formulas containing Mang Xiao

Indications & Clinical Uses

  • Constipation from interior heat, with hard dry stool and abdominal fullness
    - Mouth ulcers and swollen sore throat (used as a rinse)
    - Hot painful swellings of the skin and of the breast (used as a compress)

Western Medical Keywords

Searchable condition terms

ConstipationFecal impactionMouth ulcersBreast engorgement

Contraindications

Cautions

A strong purgative, not an everyday laxative. It is not used where there is no real accumulation to remove, and it is avoided in frail, elderly or fluid-depleted patients and in cold-type constipation. Because it dissolves as sodium sulfate it is unsuitable for anyone on sodium restriction — heart failure, kidney impairment, poorly controlled hypertension. Classical incompatibility: not combined with San Leng 三棱. Stop once the bowels move; repeated dosing depletes fluids and weakens the middle burner.

Contraindicated in pregnancy: Contraindicated in pregnancy — it purges strongly and drives downward. Also avoided while breastfeeding, since the external application is used to bring milk supply down.

For licensed practitioners’ reference only

References

  1. 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.