Educational information, not medical advice — ask your doctor or midwife.
Ardisia japonica is a small evergreen shrub from East Asia. Its dried whole plant has long been used in Chinese herbal medicine, mostly for coughs and chest complaints. In Chinese it is called ai di cha or zi jin niu.
The plant grows wild in China, Japan and Korea. It is also sold in garden centres as a ground-cover plant, sometimes called marlberry. The part used as medicine is the whole dried plant, roots included.
It appears in the official Chinese Pharmacopoeia, so it is a recognised herb there. It is not an approved medicine in the UK, the EU or the US.
Here is the honest evidence verdict. Human evidence is thin, old and of low quality. Most of what is known comes from lab dishes and animal tests.
Long use in a tradition is not proof that something works. It is also not proof that it is safe. Both points apply to this plant, and they are not repeated below.
No one has shown in good human trials how, or whether, this herb works. What follows is proposed, not proven.
The main marker compound is bergenin. In animal studies, bergenin reduced coughing and calmed swelling in tissue. Whether that happens in people taking the whole herb is not established.
In cell and test-tube studies, extracts slowed the growth of some bacteria and viruses. Lab activity like this often fails to carry over into the body.
Some lab work suggests the plant's saponins (soap-like plant compounds) can irritate cells and break down red blood cells in a dish. That is one reason stomach upset is a plausible side effect.
Traditional practice described it as clearing phlegm and "damp heat". These are ideas from inside the tradition. They are not measurable in a modern test.
It is sold and used in a few main forms.
- Dried whole herb, cut for simmering into a decoction (a strong water brew). - Powdered herb, loose or in capsules.
- Liquid extracts and tinctures. - Chinese patent cough syrups and tablets that list ai di cha among several herbs.
In the West it is hard to find on its own. Most of what you will see online is a multi-herb formula. Check the label for the Latin name, because other Ardisia species are sold under similar common names.
Chinese herbal texts recorded this plant for centuries, and it remains an official herb in China today. Records describe it in past practice as a remedy for cough with phlegm and for long-standing chest illness.
Other documented traditional uses included jaundice (yellow skin and eyes), joint and back pain, bruising after injury, and urinary complaints.
It was usually simmered with other herbs rather than taken alone. Folk use in Japan and Korea followed broadly similar lines. None of this history tells you whether the plant helped.
Stop taking it and see a doctor if you notice any of these.
- Yellow skin or eyes, dark urine, or pale stools. - Stomach pain or vomiting that does not settle. - A rash, swelling of the lips or face, or trouble breathing. - Unusual bruising or bleeding, including nosebleeds. - A cough that gets worse, brings up blood, or comes with fever and breathlessness.
Call emergency services for swelling of the throat, severe breathlessness or chest pain.
In China it is an official pharmacopoeia herb, sold as ai di cha. In the UK, the EU and the US it is not an approved medicine, and products are sold as food supplements or raw herbs with no proven health claim.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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