What is Keishikakobokukyoninto?

Keishikakobokukyoninto is a Japanese Kampo herbal formula. It is used mainly for a cough that lingers after a cold. It is also used for mild wheeze in people who tire easily, sweat readily and feel the cold.

It is one of the 148 Kampo formulas on Japan's approved list. That list is part of the MHLW (Ministry of Health, Labour and Welfare) health insurance scheme.

The recipe is the older formula Keishito with two herbs added. They are magnolia bark (koboku) and apricot kernel (kyonin).

Kampo doctors pick it for a dry or loose cough that drags on for weeks. They also pick it for asthma-type breathing in a slight, easily chilled person.

Here is the honest verdict. The formula has a long record in Kampo practice. But modern human trial evidence for it is all but absent.

A long history of use is not proof that something works. That caution applies to everything on this page. It is not repeated in each section below.

How does Keishikakobokukyoninto work?

Nobody has shown how this formula works in the body. What follows is traditional theory, not a tested mechanism (a proven way of working).

In Kampo terms, the cinnamon-twig base is said to settle a body whose surface defences are weak and leaking sweat. Magnolia bark is said to loosen a tight chest. Apricot kernel is said to send the breath downward and quiet the cough.

In modern terms, a few parts look plausible. Cinnamon twig and magnolia bark give aromatic oils. Apricot kernel gives amygdalin, which has a history of use for cough.

These parts have been studied in the lab. They have not been studied in people taking this formula.

What forms does Keishikakobokukyoninto come in?

In Japan it is most often a dried extract granule or a fine powder. A licensed maker prepares it. A doctor or pharmacist then dispenses it.

A standard pack is usually 2.5 g of granules per dose.

It is also made the old way, as a decoction. The raw herbs are simmered in water and the liquid is drunk. Some suppliers sell tablets or capsules of the same extract.

Quality matters here. The liquorice and apricot kernel content decide the safety margin. Buy only from a supplier that states the herb amounts per dose.

Where it comes from:

The recipe comes from the Shanghan Lun (Treatise on Cold Damage). This Chinese medical text was put together around the third century CE. It is credited to Zhang Zhongjing.

In that text it appears as Keishito with two herbs added. The extra herbs are magnolia bark and apricot kernel, for a patient who also has a cough.

Japanese Kampo doctors took up the Shanghan Lun formulas from about the sixteenth century on. They built their own prescribing style around body type and build.

This formula became a standard choice for the thin, easily chilled patient with a nagging cough. It is still in routine use in Japan today under the national health insurance list.

What does Keishikakobokukyoninto help with?

• Cough that lingers after a cold: This is the classic use and the reason most Kampo doctors reach for it. The traditional picture is a cough that hangs on for weeks after the fever and sore throat have gone, in someone who feels drained and chilly. There are no published controlled trials in people testing this formula for post-viral cough.
• Mild wheeze and asthma-type breathlessness: Kampo texts list this formula for mild wheeze in a person of weak build, and Japanese doctors have used it that way for generations. It is not a rescue treatment and will not open tight airways quickly. If you have asthma, keep using your prescribed inhalers and talk to your doctor before adding anything.
• Cough that gets worse in cold air: Traditional selection leans on this detail: the cough eases in a warm room and flares on going outside. That is a prescribing clue in Kampo, not a tested outcome.
• Long-running bronchitis-type cough: Used traditionally for a chesty cough that will not settle. A cough lasting more than three weeks needs a medical check first, because causes such as infection, reflux, heart problems or lung disease all need ruling out.
• Cough in a person who sweats easily and feels chilled: In Kampo the body type matters as much as the symptom. This formula is aimed at the slight, pale, easily sweating patient rather than the robust, red-faced one. That matching is traditional practice and has not been tested against placebo.

Which foods are rich in Keishikakobokukyoninto?

1. Liquorice sweets and liquorice root tea: these add to the same glycyrrhizin load as the kanzo in the formula
2. Bitter almonds and raw apricot kernels: the same amygdalin source as kyonin, and unsafe eaten loose

Practical Tips:

The formula is a prescribed herbal mixture, not a nutrient found in food; the foods listed are ones that add to its risks.

What are the side effects of Keishikakobokukyoninto?

• Rash, itching or redness of the skin
• Nausea, stomach discomfort or loss of appetite
• Loose stools
• Swelling of the face, hands or ankles from fluid build-up
• Weight gain over days to weeks from fluid build-up
• Rising blood pressure
• Muscle weakness, cramps or heaviness in the legs
• Low potassium in the blood, which can disturb heart rhythm

Good to know:

Most people who take this formula short-term have no trouble, and mild stomach upset or a rash are the usual complaints.

The serious risk comes from the liquorice root. Over weeks of use, or at higher doses, it can cause pseudoaldosteronism (a liquorice effect that copies a hormone disorder) with low potassium, swelling, high blood pressure and muscle weakness. In rare cases low potassium has led to heart-rhythm problems and severe muscle breakdown.

Older people, people on water tablets and people taking several liquorice-containing Kampo formulas at once are the most exposed.

How much Keishikakobokukyoninto should you take?

• Recommended daily: The usual Japanese adult dose of the extract granules is 7.5 g a day, split into two or three doses. Children get a reduced dose worked out by age or weight, and that should be set by a practitioner. As a decoction, the raw herb amounts vary by prescriber, so follow what you are given rather than a generic recipe. No dose has been established by clinical trial. In Japan this is a prescription product, and the safest route anywhere is to get the dose from a trained practitioner.
• Best time of day: Split the day's amount into two or three doses, spaced out — for example morning, midday and evening. Traditional practice is to take it warm.
• With or without food: Kampo extracts are traditionally taken before meals or between meals, on a fairly empty stomach. If it upsets your stomach, taking it with a little food is acceptable.
• Time to effect: If it helps, people usually notice some easing of the cough within a few days to two weeks. There is no trial data behind that timeline; it reflects normal Kampo practice.
• How long to take it: Kampo cough formulas are normally used short-term — days to a few weeks — not as a daily long-term supplement. Reassess after about two weeks. If the cough has not improved, stop and see a doctor rather than carrying on. Longer courses raise the risk from the liquorice content, so anyone taking it for more than a few weeks should have blood pressure and potassium checked.