Da Xian Xiong Tang
Do not self-treat with Da Xian Xiong Tang
Practitioner-prepared only. Where this formula is used at all, a trained Chinese medicine prescriber judges it for one person, in person, and accepts the risk.
If this is an emergency
Some reactions to Da Xian Xiong Tang need urgent care. Call your local emergency number or go to an emergency department straight away — do not wait to see whether it passes.
Who should avoid Da Xian Xiong Tang?
- Do not use if you are pregnant, as this formula can cause miscarriage
- Do not use if you are breastfeeding
- Do not use if you are under 18
- Do not use if you are elderly, frail, or already weak, thin or dehydrated (short of body water)
- Do not use if you are trying to self-treat; this formula is only for use under a trained Chinese medicine prescriber
- Do not use if you take licorice, Gan Cao, or eat licorice sweets
- Do not use if you take a diuretic (water pill), digoxin, a steroid such as prednisone, or lithium
- Do not use if you have kidney disease, liver disease or heart disease
- Do not use if you have a heart rhythm problem or have been told your potassium (a body salt) runs low
- Do not use if you have inflammatory bowel disease, a bowel blockage, or a peptic ulcer (a sore in the stomach lining)
- Do not use if you have long-term constipation, since a harsh purge is the wrong tool for it
- Do not use if you are already taking a laxative of any kind
When should you see a doctor?
Go to hospital or call emergency services now if you cannot stop vomiting or passing watery stools, if you feel faint, if your heart pounds or skips, if you stop passing urine, or if your belly pain becomes severe or your belly turns rigid.
See a doctor the same day if you feel very weak, thirsty or dizzy after taking it, or if your muscles cramp badly.
See a doctor before taking anything if you have belly pain with fever, vomit blood, pass black or bloody stools, or have lost weight without trying.
- What it is: A classical Chinese herbal formula of rhubarb root, mineral salt and toxic kansui root that acts as a very strong purge.
- Active ingredients: Anthraquinones from Da Huang (sennosides, rhein, emodin), Sodium sulfate from Mang Xiao, Diterpene esters from Gan Sui (kansuinines, ingenol-type esters)
- Side effects: Cramps and heavy diarrhoea are expected; dehydration, low potassium and Gan Sui poisoning are the real dangers.
- Pregnancy & breastfeeding: Avoid in pregnancy and while breastfeeding.
Educational information, not medical advice — ask your doctor or midwife.
What is Da Xian Xiong Tang?
Da Xian Xiong Tang is a classical Chinese herbal formula, also known as Major Sinking into the Chest Decoction. It is a very strong purge, which means it forces the bowels to empty fast and pulls water out of the body. In Chinese medicine it is given for a hard, full, painful chest and upper belly with blocked bowels.
This entry covers a single drug (TCM formula). It holds three herbs: Da Huang (rhubarb root), Mang Xiao (mirabilite, a mineral salt), and Gan Sui (kansui root). Gan Sui is a toxic plant, and the formula is made and dosed by a trained Chinese medicine doctor only.
The honest verdict: this formula has a long record in Chinese medicine, but we found no reliable human trials of it. Long traditional use is not proof that something works or that it is safe. It is not a home remedy, and it is not for everyday constipation.
How does Da Xian Xiong Tang work?
Each of the three herbs acts on the gut, and together they empty it hard and fast.
Da Huang (rhubarb root) holds compounds called anthraquinones that make the bowel wall squeeze and push. Mang Xiao is a sulfate salt that draws water into the bowel and softens hard stool. Gan Sui irritates the lining of the gut and pulls fluid into it, which is also the reason it is toxic.
Most of this comes from lab and animal work on the single herbs. It explains why the formula causes a strong bowel movement. It does not prove that the whole formula treats any named illness.
What forms does Da Xian Xiong Tang come in?
The classic form is a decoction, which is a strong tea boiled from the herbs. Da Huang and Mang Xiao are boiled, and the Gan Sui is stirred in as a raw powder at the end rather than boiled.
Some suppliers sell it as granules or pills made for prescribers. It is not a normal shop or online supplement, and it is controlled or restricted in many countries because Gan Sui is toxic.
If you are offered this formula without a trained prescriber checking you first, do not take it.
Where it comes from:
The formula comes from the Shang Han Lun (Treatise on Cold Damage), written by Zhang Zhongjing in China around 200 CE. It is one of the best-known purging formulas in that book. It has been taught and used in Chinese medicine ever since, which makes it a long-standing staple of one tradition.
What does Da Xian Xiong Tang help with?
- Hard, full, painful chest and upper belly with blocked bowels: This is the one pattern the formula was written for. The chest and upper belly feel hard and full. They hurt when pressed, and the bowels do not move. The use comes from classical texts and from teaching passed down since then. We found no trials that test it. A trained Chinese medicine doctor must judge whether the pattern fits before anyone takes it.
- Severe short-term constipation with a tight, sore belly: This is not a daily laxative. It is a harsh purge meant for one dose in a severe, short-lived blockage. Mild or long-term constipation needs gentler and safer help, such as more fluid, more fibre, or a standard laxative from a pharmacy. We found no human trials of this formula for constipation. A belly that stays hard, sore and blocked needs a doctor, not a stronger purge.
- Fluid stuck in the chest or belly: Old texts describe using this formula to drive out fluid held in the chest or belly. Gan Sui pulls water into the gut, which is the idea behind that use. We found no human studies that test it for this. Fluid in the chest or belly is often a sign of heart, liver, kidney or lung disease. Those need proper tests and care, so see a doctor first.
- Sudden severe belly pain treated in hospital, such as pancreatitis: Some hospitals in China have used this formula, or changed versions of it, next to normal medical care for sudden belly pain. Reports are small and mostly in Chinese. We could not identify a well-run trial, so this stays unproven. Sudden severe belly pain is an emergency. Go to hospital or call emergency services; do not treat it at home.
What are the side effects of Da Xian Xiong Tang?
- Strong belly cramps and griping pain
- Heavy watery diarrhoea
- Nausea and vomiting
- Dehydration (losing too much body water)
- Loss of body salts, especially low potassium (a salt your heart and muscles need)
- Dizziness, weakness or fainting from low blood pressure
- Burning or soreness in the mouth and throat from Gan Sui
- Kidney strain if you become dry and depleted
- Miscarriage or harm to a pregnancy
- Bowel that stops working on its own, and dark staining of the bowel lining, if rhubarb-type purges are used repeatedly
Good to know:
Cramping and heavy watery stools are expected, not rare; that is what the formula does. The danger is what follows. Losing that much fluid and salt can drop your blood pressure, upset your heart rhythm and strain your kidneys.
Gan Sui poisoning has caused severe vomiting, collapse and deaths when the dose was too high or the herb was self-prescribed. This is why the formula sits in the high-risk group and belongs only in trained hands.
Options to discuss with a clinician
Better-studied routes exist for each of the problems this formula is reached for, and every one of them starts as a conversation with a doctor, pharmacist or qualified herbalist rather than a swap you make at home.
**Fluid building up in the chest or belly.** This is not a self-treatment problem. Fluid collecting around the lungs or in the abdomen points to the heart, liver or kidneys, and needs a doctor to find the cause and manage it — drainage and prescribed water tablets are the studied routes here.
**Sudden severe belly pain, or suspected pancreatitis (a swollen pancreas gland).** Emergency assessment, not a remedy. Hospital care for this is well established.
**Constipation with a tight, sore belly.** Ask a pharmacist or doctor which of the well-evidenced options suits you: Psyllium Husk, Supplemental fiber, Inulin, Magnesium, or Probiotics are all commonly discussed. Where cramping is the main complaint, Peppermint Oil is worth raising. Senna (Unani) is a short-term stimulant laxative a pharmacist can advise on.
**Comfort alongside medical care.** Massage Therapy and Acupressure are sometimes offered; mention them to your clinician so they fit with your treatment.
Graded pages for the options named above:
- Supplemental fiber — evidence grade A, traditional tier T0
- Massage Therapy — evidence grade B, traditional tier T3
- Peppermint Oil — evidence grade A, traditional tier T2
- Psyllium Husk — evidence grade A, traditional tier T3
- Senna (Unani) — evidence grade A, traditional tier T3
- Acupressure — evidence grade B, traditional tier T3
- Probiotics — evidence grade A, traditional tier T0
- Magnesium — evidence grade A, traditional tier T0
- Inulin — evidence grade A, traditional tier T0
Review status
This page has not been signed off by a pharmacist and is not published. It is shown here for a policy decision only.