Yijintang

What is Yijintang?

Yijintang is a herb mix used in Korean traditional medicine. The name means "two aged decoction." Healers gave it for a wet cough, a heavy or full chest, and a queasy stomach.

It is not one herb. It blends aged pinellia root and aged citrus peel with poria, licorice and fresh ginger. The two "aged" herbs give the mix its name.

Long use does not prove that a remedy works. The record of use here is strong, but the human trial evidence is weak. We found no large, good quality trial in people that we can point to.

How does Yijintang work?

In old Korean medicine, the mix is said to dry "damp phlegm" and settle the stomach. That is a traditional idea, not a lab finding.

Lab and animal work gives a few hints. Citrus peel and ginger may calm the gut and ease nausea. Licorice may soothe a sore, irritated throat.

We do not know if these effects hold in people at tea-strength doses. No study has shown how the whole mix acts in the body.

What forms does Yijintang come in?

Most people take it as a hot tea. You simmer the cut herbs in water, then strain and drink the liquid.

It also comes as granules, powder, capsules or a ready-made drink. Granules melt in hot water. Products vary a lot in strength, so read the label.

Where it comes from:

The recipe first appears in a Chinese book of set formulas from 1107. Korean doctors took it up and used it widely.

Heo Jun listed it in the Donguibogam of 1613, a key Korean medical text. It is still one of the best known phlegm formulas in Korea, China and Japan.

What does Yijintang help with?

• Wet cough with thick phlegm: This is the classic use. Korean texts give it for a loose, rattling cough with white or clear phlegm, not a dry cough. Human trial support is thin, and we found no trial we can cite by name.
• Nausea and vomiting: Tradition uses it for queasiness that comes with a full, damp stomach. Ginger on its own has some human evidence for nausea. That does not prove the whole mix works the same way.
• Feeling full or heavy in the chest and stomach: Practitioners give it for a stuffed, heavy feeling after eating. This use rests on tradition and on practitioner reports, not on controlled trials in people.
• Poor appetite with a coated tongue: A thick white tongue coating is a traditional sign that guides its use. There is no modern test of this sign, and no trial that measures appetite as an outcome.
• Dizziness linked in tradition to "phlegm": Some classical texts use it for dizziness with nausea. Dizziness has many causes, some of them serious. Get checked by a doctor before treating dizziness with herbs.

Which foods are rich in Yijintang?

1. Dried tangerine peel: the same aged citrus peel used in the mix, common in Korean and Chinese cooking
2. Fresh ginger: the same herb, used in soups, tea and marinades
3. Licorice root sweets: a source of glycyrrhizin, the compound that can raise blood pressure

Practical Tips:

If you eat licorice sweets often, count them towards your licorice intake while taking this mix.

What are the side effects of Yijintang?

• Dry mouth or thirst
• Upset stomach or loose stools
• Heartburn from the ginger and peel
• Puffy face, hands or ankles from the licorice
• Raised blood pressure with longer use
• Low potassium (a blood salt), which can cause muscle weakness or cramps
• Burning or swelling of the mouth and throat if raw, unprocessed pinellia is used
• Rash or itching from an allergy to any herb in the mix

Good to know:

Short-term use of a properly made product is usually well tolerated. Mild dry mouth or stomach upset is the most common complaint.

The real risk comes from the licorice. Over weeks, it can raise blood pressure, cause swelling and lower potassium, which can upset your heart rhythm.

Raw pinellia root is harmful and can badly irritate the mouth and throat. Only processed pinellia belongs in this mix.

How much Yijintang should you take?

• Recommended daily: There is no dose proven by modern research. Doses below come from traditional practice and from product labels. A common daily tea uses about 6 g processed pinellia, 6 g aged citrus peel, 4 g poria, 2 g licorice and a few slices of fresh ginger. That day's batch is split into two or three drinks. Granule products usually give 2 g to 6 g a day, split into two or three doses. Follow the label, or a Korean medicine practitioner's advice.
• Best time of day: Usually two or three times a day, spread out. Some practitioners give the last dose well before bed, since the warm, spicy taste can be stirring.
• With or without food: Usually taken warm between meals, or about 30 minutes before eating. If it upsets your stomach, take it with a little food.
• Time to effect: Traditional reports say nausea and chest fullness may ease within a few days. Cough and phlegm are said to take one to two weeks. None of this is backed by trial data.
• How long to take it: Traditional use is short. Most practitioners use it for a few days up to about two weeks for a cough or a bout of nausea. Stop and get advice if nothing changes after two weeks. Because of the licorice, do not take it for more than four weeks without a practitioner watching you.