Heat in the lower body
The core idea's Heat that's settled low down, with a heavy, uncomfortable feeling to it.
Traditional Japanese Kampo formula
Yi Zi Tang
乙字汤 · Otsuji's Formula · also known as Otsujito
The odd one out in our range: Yi Zi Tang was created in Japan, not China. It's a Kampo formula from the Edo period, built from Chinese herbs, and herbalists used it for Heat and a heavy, dragging feeling in the lower body.
Five herbs, led by a big dose of bupleurum, with dong quai, Baikal skullcap, liquorice and a little rhubarb root. Made into 5:1 tablets. Six a day, so a bottle lasts ten days. Explore the formula
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- 5:1 strength
- DaoDi herbs
- Vegan & gluten-free
- GMP certified
- Free UK delivery £40+
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A short history of Yi Zi Tang
Yi Zi Tang is just the Chinese reading of Otsujito, a formula worked out by Hara Nanyo, a physician in Edo-period Japan who lived from 1752 to 1820. By then Japanese doctors had been studying Chinese medicine for centuries and had grown their own version of it, Kampo, and this is one of Kampo's home-grown classics.
Despite the English 'Otsuji's Formula' (we use it too, so no judgement), the name's got nothing to do with a person. Otsu (乙) is the second of the ten Heavenly Stems, an old Chinese counting system a bit like A, B, C, and Hara Nanyo labelled some of his formulas that way. So it's 'Formula B', more or less. Bit of an anticlimax, isn't it?
He built it for complaints of the lower body, with haemorrhoids top of the list in the Kampo books of the day. Later Japanese doctors tweaked it, and today's standard Kampo version includes cimicifuga as well. Ours is a five-herb version without it, and bupleurum's very firmly in charge.
In Chinese medicine
How herbalists understand it
The thinking is that two things are happening low down at once. Heat's built up, and Qi, which ought to be holding things up and in place, has started to sag. Hot and heavy, if you like. Kampo doctors saw it a lot in people who sat about for long hours.
So the formula pulls two ways at the same time. Bupleurum, at a big dose, is the classic lifting herb, said to raise sinking Qi, while Baikal skullcap and rhubarb root clear Heat and move things downwards and out. Sounds contradictory, doesn't it? A herbalist would just call it balance.
Dong quai nourishes and moves Blood, because wherever there's Heat and sluggishness, Blood's thought to pool. Liquorice, at a fair dose, keeps everything in harmony and softens the sharper herbs. Only five herbs in all, which is very Japanese in its economy.
The Five Elements
A Wood element formula
Bupleurum, the chief herb here, belongs to the Liver, and the Liver belongs to Wood, the element of spring and of growing upwards. That upward push is exactly why bupleurum's in the formula.
Spring
Season
Wood's season, when everything rises, and bupleurum's the herb of rising.
Liver
Organ
The Liver channel runs through the lower body, which is just where this formula focuses.
Green
Colour
Wood's colour. Before the root's dug up, bupleurum is a feathery green plant with little yellow flowers.
Sour
Taste
That's Wood's taste, though this formula leans bitter instead, thanks to the skullcap and rhubarb.
Anger
Emotion
Wood's emotion, and herbalists say frustration that's bottled up can turn into Heat.
Traditional use
How it has traditionally been used
This is how Kampo and Chinese herbalists have traditionally used it. It's traditional practice, so please don't read it as a medical claim.
Sinking Qi
Picked when things feel like they're dragging down, not holding up.
Long hours sitting
Kampo doctors linked the pattern with desk-bound, sit-down lives.
Sluggish with Heat
In Kampo terms, it's chosen when slowness and warmth turn up together.
This section describes traditional use in Chinese herbal practice. Yi Zi Tang is a food supplement and is not intended to diagnose, treat, cure or prevent any disease.
Inside the formula · Ingredients
Five herbs, lifting and clearing
Kampo formulas follow the same royal court idea as Chinese ones: a chief, ministers, an assistant and an envoy. Amounts are per daily serving of 6 tablets.
Chief
Bupleurum Root (Chai Hu)
Bupleurum chinense1246mg
Bupleurum chinense1246mg
Bupleurum's the biggest amount by a long way, and herbalists use it to lift sinking Qi and ease the Liver. Herb Glossary
Ministers
Baikal Skullcap Root (Huang Qin)
Scutellaria baicalensis471mg
Scutellaria baicalensis471mg
Dong Quai Root (Dang Gui)
Angelica sinensis942mg
Angelica sinensis942mg
Baikal skullcap, a bright yellow root once it's sliced, clears Heat, and dong quai nourishes and moves Blood. Herb Glossary
Assistant
Rhubarb Root (Da Huang)
Rheum officinale236mg
Rheum officinale236mg
A small amount of rhubarb root clears Heat and moves things downwards. Herb Glossary
Envoy
Liquorice Root (Gan Cao)
Glycyrrhiza glabra471mg
Glycyrrhiza glabra471mg
Liquorice keeps things in harmony and takes the edge off all the bitter herbs. Herb Glossary
Inactive ingredients: Cassava starch, Hypromellose, Magnesium stearate, Polyethylene glycol, Talc.
These are used in very small amounts to form and coat the tablets. They don't add to the formula itself.
How to take
A simple daily ritual
3In the morning
Tablets with water.
3In the evening
Tablets with water.
WeeksSteady use
Most people take a formula for several weeks.
Always follow the label. If you take any medication, are pregnant or breastfeeding, please speak to your GP or pharmacist before use.
Choosing between them
Yi Zi Tang or Xiao Chai Hu Tang?
| Compare | Yi Zi Tang | Xiao Chai Hu Tang |
|---|---|---|
| First recorded | Edo Japan, around 1800 | Eastern Han, around 200 AD |
| The idea | Lift sinking Qi and clear Heat low down | Harmonise the 'half inside, half outside' level |
| Herbs | 5, including rhubarb root | 7, including ginseng and pinellia |
| Character | Cooling and lifting | Balanced, harmonising |
| Often chosen when | Heat and heaviness sit in the lower body | Things swing back and forth and won't settle |
Is Yi Zi Tang Chinese or Japanese?
Japanese. Hara Nanyo put it together in Edo-period Japan using Chinese herbs and Chinese theory, and Yi Zi Tang is just the Chinese reading of its Japanese name, Otsujito.
Who was Otsuji?
Nobody, as it turns out. Otsu's the second of the ten Heavenly Stems, so the name means something like 'Formula B', and the English version simply grew legs.
Why is there no cimicifuga?
Plenty of modern Kampo versions do include it. Ours is a five-herb version that leans on a bigger dose of bupleurum to do the lifting instead.
How many do I take?
You'd take three in the morning and three in the evening, and a bottle lasts ten days.
Can I take it long-term?
There's rhubarb root in it, so it's traditionally taken for shorter spells. If your bowel habits have changed and haven't settled back down, please see your GP instead of relying on a supplement.
Is it safe in pregnancy or with medication?
Pregnant or breastfeeding? Then please avoid it, mainly because of the rhubarb and dong quai. Anyone on blood thinners like warfarin should skip it too (that's the dong quai), and the liquorice isn't advised with high blood pressure. Formulas with bupleurum and Baikal skullcap have, rarely, been linked to liver reactions, so leave it if you've got liver problems. And if you take any regular medicine, check with your GP or pharmacist first.
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Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. Not intended to diagnose, treat, cure or prevent any disease. Keep out of reach of children.