Educational information, not medical advice — ask your doctor or midwife.
Otsujitokyodaio is a Japanese Kampo herbal formula used for piles (haemorrhoids). It is the classic Otsujito recipe with the rhubarb root left out. In Japan it is a ministry-approved Kampo medicine, supplied by makers such as Tsumura.
The name says what it is. "Kyo daio" means "rhubarb removed". Without rhubarb, the strong bowel-moving part of the original formula is gone.
People take it for anal pain, itching, swelling and minor bleeding from piles. It suits those who would get loose stools from the rhubarb version.
Evidence verdict: the formula is a long-standing Kampo staple, but good human trials are missing. Traditional use is not proof that a medicine works, and that applies here.
The honest answer is that its action in people is not well worked out.
Kampo theory says the formula lifts sunken energy and clears heat and swelling in the lower body. That is a traditional idea, not a measured effect.
In cell and animal studies, several of its herbs show anti-inflammatory activity. Baicalin from ogon and saikosaponins from saiko act this way in the laboratory. Whether that eases piles in people has not been shown.
Some Kampo teaching says the formula supports the tone of the tissue around the anus. No human study has tested that claim.
It comes mainly as a dry granule or powder in single-dose sachets. This is the usual Kampo extract form used in Japan.
Tablets and capsules of the same extract are also made. Some pharmacies supply the raw herbs for a decoction you boil at home.
In Japan it is prescribed by doctors and sold in pharmacies. Outside Japan it is much harder to find, and product quality varies.
Otsujito is a Japanese formula, not a Chinese classic. The Edo-period doctor Hara Nanyo created it in the early 1800s.
He built it for piles, anal fissure (a small tear in the anal lining) and prolapse. The rhubarb-free version was shaped for people who do not need a laxative effect.
It stays in daily use in Japanese Kampo practice today. Its standing rests on long clinical custom, not on trial data.
Some reactions to Otsujitokyodaio need urgent care. Call your local emergency number or go to an emergency department straight away — do not wait to see whether it passes.
Stop the formula and get urgent medical help if you have severe muscle pain or weakness. Dark brown urine with muscle pain can mean muscle breakdown, which harms the kidneys. Call emergency services if you have an odd or racing heartbeat, chest pain, or trouble breathing.
See a doctor soon if your ankles, face or hands swell. Do the same if your blood pressure rises, or if you feel very tired or have cramps.
See a doctor before you start if you bleed from the back passage. Bleeding needs a diagnosis, and it is not always piles. Also see a doctor if pain, lumps or bleeding last more than two weeks.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
Reviewed by the HealisticMD editorial team How we grade evidence →
The published evidence for Otsujitokyodaio is weak or absent. That usually means no controlled trial has tested it, not that a trial found it ineffective — the two are different, and we grade only what has been published.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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