What is Koshaheiisan?
Koshaheiisan is a Japanese Kampo herbal formula for a heavy, bloated, sluggish stomach. It is used for fullness after meals, poor appetite, nausea and loose stools. Japan's health ministry approves it as a Kampo medicine, and Tsumura is one of the makers.
It is the classic Heiisan base with two extra herbs. The base is Atractylodes lancea root, magnolia bark, citrus peel, licorice root, ginger and jujube. To that it adds cyperus root and amomum fruit.
Here is the honest verdict. The formula has long standing in Kampo practice, but we could not find human trials of it. Long use in a tradition is not the same as proof of effect.
One safety point shapes the whole page. The licorice in it can raise blood pressure and drop your potassium. That is covered in full below.
How does Koshaheiisan work?
No one has shown in people how this formula works. What follows is theory plus laboratory work.
Kampo theory describes it as warming and drying a "damp", heavy stomach. Cyperus and amomum are said to get a stalled stomach moving again. That is a traditional idea, not a measured effect.
Some single herbs have been studied in the lab. In animal and cell work, ginger and citrus peel appear to speed stomach emptying. Magnolia bark compounds relax gut muscle in test-tube studies.
One mechanism is well established in people, and it is a risk, not a benefit. Glycyrrhizin from licorice blocks an enzyme called 11-beta-HSD2, which normally shields the kidney's salt switch. The result can be pseudoaldosteronism (a salt and potassium imbalance): the body holds salt and water, loses potassium, and blood pressure rises.
What forms does Koshaheiisan come in?
Most people in Japan take a dried extract granule, sold in single-dose sachets.
Other forms exist. Some makers press the same extract into tablets or fill capsules. Traditional practitioners may also cook the raw herbs into a tea (a decoction).
Granules are the form used in Japanese hospital and pharmacy practice, and the form most dosing advice refers to.
Where it comes from:
Heiisan is an old Chinese formula, written down in the Song dynasty Taiping Huimin Heji Jufang, around 1100 CE. Adding cyperus and amomum gives Koshaheiisan, known in Chinese as Xiang sha ping wei san.
Japanese Kampo doctors adopted it and have used it for centuries for weak, damp digestion. Japan now lists it among its approved Kampo medicines, which is a regulatory listing, not a finding of proven benefit.
If this is an emergency
Some reactions to Koshaheiisan 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 Koshaheiisan?
- Do not use if you have low blood potassium (hypokalaemia).
- Do not use if you have been told you have aldosteronism, a hormone problem that raises blood pressure.
- Do not use if you have myopathy, a disorder of weak or wasting muscles.
- Do not use if you are already taking another licorice product, including glycyrrhizin injections or another Kampo formula with licorice.
- Do not use if you have high blood pressure, heart failure or a heart-rhythm problem, unless your doctor supervises you and checks your potassium.
- Do not use if you have kidney disease or liver disease, unless your doctor supervises you.
- Do not use if you take water pills (diuretics) or steroid medicines, unless your doctor is checking your blood.
- Do not use if you are pregnant or breastfeeding, unless a doctor who knows Kampo has advised it.
- Do not use if you are giving it to a child, unless a children's doctor has set the dose.
- Do not use if you have ongoing, severe or bloody diarrhoea, black stools, or unexplained weight loss; get those checked first.
When should you see a doctor?
Stop the formula and call your doctor if your ankles, hands or face swell, if you gain weight fast, or if your muscles feel weak, sore or crampy. These can be signs that your potassium has dropped.
Also call if your blood pressure climbs, you get bad headaches, your skin or eyes turn yellow, or your urine goes dark.
Get emergency help for an irregular or racing heartbeat, fainting, chest pain, or severe muscle weakness that you cannot walk on.
4.8
