Inchinkoto

What is Inchinkoto?

Inchinkoto is one of the oldest surviving prescriptions in East Asian medicine. It appears in the Shanghan Lun, a Chinese clinical text compiled around 200 CE, as Yin Chen Hao Tang, and it entered Japanese Kampo practice largely unchanged. It contains just three ingredients: the aerial parts of Artemisia capillaris (inchinko), the fruit of Gardenia jasminoides (sanshishi), and rhubarb rhizome (daio).

In traditional terms it treats "damp-heat jaundice" — a picture of yellowed skin and eyes, dark concentrated urine, fullness in the upper abdomen, thirst and constipation. In modern Japan it is not a general-purpose supplement. It is a prescription Kampo product, most often given in hospital settings to people with cholestasis, obstructive jaundice, biliary atresia, or after liver resection, alongside conventional care rather than instead of it.

What sets it apart from most traditional formulas is the amount of laboratory work behind it. Japanese researchers have studied how genipin, formed in the gut from gardenia's geniposide, stimulates bile secretion through a bile transporter in liver cells. That mechanism is reasonably well described. The human clinical picture is much thinner: small controlled trials, retrospective hospital series and case reports, mostly from Japan, with inconsistent designs. Jaundice always needs a diagnosis first — this is a formula to discuss with a doctor, not one to self-prescribe.

How does Inchinkoto work?

The best-characterised action comes from gardenia. Its geniposide is converted by gut bacteria into genipin, which increases the movement of bile out of liver cells by acting on the MRP2 bile transporter — a choleretic effect demonstrated repeatedly in animal and cell studies. Artemisia capillaris contributes coumarins such as scoparone and 6,7-dimethylesculetin, which in laboratory models reduce liver inflammation and promote bilirubin clearance. Rhubarb adds anthraquinones that stimulate the bowel, which traditional theory frames as 'draining heat downward' and which in practice means a laxative effect. Whether these mechanisms translate into meaningful clinical benefit in people is exactly the question that the existing small trials have not settled.

What forms does Inchinkoto come in?

In Japan the dominant form is a standardised granulated hot-water extract dispensed by prescription — Tsumura TJ-135 is the most widely used and the one appearing in most published studies. This matters, because the extract has a fixed ratio of the three herbs and a consistent geniposide content, whereas raw-herb decoctions vary with sourcing and preparation. Tablets and capsules of the extract also exist. Traditional decoction, simmering the raw herbs and drinking the liquid, is still used by some practitioners. Outside Japan, products sold as Yin Chen Hao Tang follow the same three-herb formula but quality control is far less predictable.

Where it comes from:

The formula is attributed to Zhang Zhongjing and recorded in the Shanghan Lun around 200 CE, where it is prescribed for jaundice with fever, thirst, abdominal fullness and constipation. It travelled to Japan with Chinese medical texts and became a standard entry in Kampo formularies, retained through the Edo period and into modern Japanese medicine. Since the 1970s, when Kampo extract granules were brought into Japan's national health insurance system, Inchinkoto has been prescribed in hospitals — notably in hepatobiliary surgery and paediatric liver disease — making it one of the few classical formulas with a continuous presence in mainstream hospital practice.

What does Inchinkoto help with?

• Jaundice (as a supervised adjunct): Jaundice is the formula's classical indication and the reason it has survived for eighteen centuries. In modern Japan it is sometimes added to conventional treatment for cholestatic jaundice, and small hospital series report falls in bilirubin. These reports are mostly uncontrolled, so it is impossible to separate the formula's effect from the natural course of the underlying illness. Jaundice always has a cause — gallstones, hepatitis, drug injury, tumour — that must be identified. Inchinkoto is not a substitute for that workup, and self-treating yellowed skin or eyes with a herbal product is genuinely dangerous.
• Cholestasis and impaired bile flow: This is where the mechanistic case is strongest. Genipin, produced in the gut from gardenia's geniposide, has been shown in animal and cell studies to increase bile secretion through the MRP2 transporter, and Artemisia constituents add further choleretic activity. Small Japanese clinical studies in cholestatic patients have reported improvements in bilirubin and bile output. The trials are few, small and not consistently blinded, so the honest summary is: a plausible and well-described mechanism with preliminary human data behind it, not a demonstrated clinical benefit.
• Recovery after liver resection: Inchinkoto has been given perioperatively in some Japanese centres to patients undergoing hepatectomy, with the idea that improved bile flow and reduced liver inflammation might protect the remaining liver. Published work includes small randomised and retrospective comparisons reporting better postoperative liver blood tests or fewer biliary complications. The studies are single-country, modest in size, and their outcome measures differ, which is why the practice has not spread beyond Japan. It is a hospital decision made by a surgical team, not something a patient adds on their own.
• Biliary atresia after Kasai surgery: Japanese paediatric hepatology has used Inchinkoto in infants after the Kasai portoenterostomy, aiming to support bile drainage. The evidence is limited to case series and retrospective reviews from a handful of centres, with no large controlled trial. Dosing in infants is a specialist matter, weight-based and monitored, and includes attention to the rhubarb component's effect on the bowel. This use is mentioned here because it exists in the literature, not as a suggestion — it belongs entirely to specialist paediatric care.
• Constipation with a 'damp-heat' pattern: The rhubarb in the formula reliably produces a laxative effect, and in Kampo terms this is part of the treatment rather than a side effect: constipation with abdominal fullness, dark urine and a greasy yellow tongue coating is one of the pattern signs a practitioner looks for. But Inchinkoto is a poor choice as a plain laxative. Stimulant anthraquinones cause cramping, can lower potassium, and lose effect with prolonged daily use. Gentler options exist for straightforward constipation.
• Hepatic fibrosis and liver inflammation: Laboratory studies in cultured cells and rodent models of liver injury have reported that Inchinkoto and its individual constituents reduce markers of inflammation and stellate-cell activation, the process underlying fibrosis. This work is frequently cited in reviews and is genuinely interesting, but it is preclinical. There is no adequate human trial showing that taking Inchinkoto slows fibrosis in people with chronic liver disease. Anyone with hepatitis, fatty liver disease or cirrhosis should treat this as a hypothesis, not a treatment option, and follow their hepatologist's plan.

What can Inchinkoto help prevent?

• Nothing is established. Preventive claims for this formula rest on preclinical work and small hospital series.
• Postoperative liver dysfunction after hepatectomy: small Japanese studies have explored this, with mixed and inconclusive results.
• Progression of liver fibrosis: supported only by animal and cell studies, not by human trials.

Which foods are rich in Inchinkoto?

There is no food that reproduces Inchinkoto — it is a concentrated herbal extract with a laxative component. For general liver and bile support alongside medical care, the sensible dietary moves are: keep alcohol low or absent, since it is the single biggest modifiable liver stressor; eat plenty of soluble fibre from oats, beans and vegetables, which binds bile acids and supports their turnover; include cruciferous vegetables (broccoli, cabbage, daikon), which contain compounds that support liver detoxification enzymes; get enough water, especially if the rhubarb is loosening stools; and eat regular moderate meals rather than very large fatty ones, which can trigger pain in gallbladder disease. If you are taking Inchinkoto, potassium-rich foods — bananas, potatoes, leafy greens, beans — help offset losses from the laxative effect. Foods to limit: alcohol, very high-fat fried meals if you have gallstones, and other stimulant laxative products such as senna tea, which stack with the rhubarb.

What are the side effects of Inchinkoto?

• Loose stools or diarrhoea: the most common effect, from the rhubarb
• Abdominal cramping and colicky pain
• Nausea or loss of appetite
• Low potassium with prolonged laxative use, which can cause weakness, cramps or palpitations
• Rare but important: mesenteric phlebosclerosis after long-term (typically multi-year) use of gardenia-containing Kampo formulas, causing chronic abdominal pain, bloating, diarrhoea and in severe cases bowel obstruction
• Rare drug-induced liver injury has been reported with Kampo products generally, which is confusing in a formula used for liver problems and is one reason monitoring matters
• Rare allergic skin reactions
• Very rare interstitial pneumonia has been reported with some Kampo formulas — new persistent cough, breathlessness or fever warrants stopping and seeking care

Good to know:

Inchinkoto contains no licorice, so the pseudoaldosteronism risk common to many Kampo formulas does not apply directly — but the rhubarb can still deplete potassium in its own way. The two safety issues that genuinely matter are the stimulant laxative action of daio and the long-term gardenia risk. Neither is a reason to avoid short supervised use; both are reasons not to take it indefinitely.

How much Inchinkoto should you take?

• Recommended daily: In Japan the standard adult prescription of the granulated extract (e.g. TJ-135) is 7.5 g per day, divided into two or three doses. Traditional decoctions vary. Because the formula is used for conditions that require diagnosis — jaundice, cholestasis, biliary disease — the dose should be set and monitored by a doctor or a trained Kampo practitioner, and reduced if stools become loose.
• Best time of day: Divided across the day, conventionally before or between meals. Kampo granules are traditionally dissolved in hot water and sipped.
• With or without food: Traditionally taken on an empty stomach, roughly 30 minutes before meals or between them. If it causes stomach discomfort, taking it with a little food is reasonable and unlikely to matter much.
• Time to effect: The bowel effect from rhubarb usually appears within 6–24 hours. Changes in bilirubin or liver enzymes, where they happen, are judged over one to several weeks with blood tests.
• How long to take it: Short courses under supervision. Continuous long-term use is discouraged: the rhubarb component causes tolerance and electrolyte loss, and years of gardenia-containing formulas have been linked to mesenteric phlebosclerosis. If it is being used beyond a few weeks, that should be a deliberate medical decision with periodic review of bloods and bowel symptoms.