Soshikokito

What is Soshikokito?

Soshikokito is a Kampo herbal formula taken for a long-standing cough with phlegm and for breathlessness. In Japan it is a Ministry-approved Kampo formula, made by firms such as Tsumura. Its name is often given in English as Perilla Fruit Decoction for Directing Qi Downward.

It is chosen by pattern, not by test result. Kampo practice points it at a person whose chest feels full and tight while the legs and feet feel cold. It is used most in older or run-down people with a wet, rattling cough.

Here is the plain verdict. The formula has centuries of recorded use behind it. Good human trials of the formula itself are lacking, and traditional use is not proof that it works.

How does Soshikokito work?

How it works in the body has not been shown clearly in people. Kampo theory says it turns rising qi (vital energy) back downward and clears phlegm. That is a traditional idea, not a measured effect.

Some single herbs in it have been studied alone. In lab and animal tests, perilla fruit and magnolia bark appear to relax airway muscle. Whether that happens in a person taking the whole formula is not known.

One effect is well established in people, and it is unwanted. Licorice root (kanzo) contains glycyrrhizin. Glycyrrhizin blocks a kidney enzyme called 11-beta-hydroxysteroid dehydrogenase type 2.

Blocking that enzyme lets the body hold salt and water and lose potassium. Blood pressure can rise as a result. This is a drug-like effect, and it is the reason the formula needs care.

What forms does Soshikokito come in?

The usual form is a dried extract granule in a sealed sachet. Tablets and loose powders are also sold.

A traditional decoction is another option. You simmer the raw herbs in water and drink the strained liquid. Granules are far more common now, because the dose is fixed and easier to check.

Where it comes from:

The recipe comes from a Chinese state pharmacy text of the Song era, the Taiping Huimin Heji Ju Fang, printed in the early 1100s. It is known in Chinese medicine as su zi jiang qi tang.

Japanese doctors took it up and kept it in use for centuries. Today it sits on Japan's approved list of Kampo prescriptions. So it has classical standing in two linked traditions.

What does Soshikokito help with?

• Long-standing cough with phlegm: This is the classic use. Kampo texts recommend it for a wet cough that drags on in a weak or older person. We found no good human trial that tests this use.
• Wheezing and breathlessness: Traditional use is strong here, and the formula was built for it. Lab and animal work on single herbs hints at airway relaxing effects. That has not been confirmed in people taking the formula.
• Chronic bronchitis (long-term swelling of the airways): Japanese and Chinese practice use it for a damp, phlegmy cough of this kind. Published human evidence is limited to case reports and small uncontrolled reports. Treat it as unproven.
• Asthma, as an add-on to standard care: It is sometimes given alongside inhalers in Kampo practice. It is not a rescue treatment and does not replace one. Never stop an asthma inhaler in order to try it.
• Cough in COPD (a long-term lung disease): Some Japanese doctors use it for cough and chest fullness in this setting. Trial evidence to support that is thin. Fluid retention from licorice can be a real problem in people with heart or lung strain.
• Chest fullness with cold legs, a Kampo pattern: This is the pattern the formula is matched to. It is a traditional way of sorting people, not a medical diagnosis. It has no test to confirm it.

Which foods are rich in Soshikokito?

1. Licorice sweets and licorice root tea: these add more glycyrrhizin on top of your dose
2. Perilla (shiso) seeds and leaves: the same plant family as the lead herb
3. Fresh and dried ginger: a minor herb in the recipe
4. Cinnamon bark: used as a spice and as a herb here
5. Jujube (red date): eaten as a dried fruit in East Asia

Practical Tips:

Eating the food forms is not the same as taking the formula, but licorice sweets and licorice tea do add real risk.

What are the side effects of Soshikokito?

• Low potassium in the blood (hypokalaemia)
• Swollen ankles or puffy face from held-on water
• Rising blood pressure
• Quick weight gain over days, from fluid
• Muscle pain, cramps or weakness
• Dark or cola-coloured urine, a sign of muscle breakdown
• Headache
• Nausea, stomach upset or loose stools
• Rash or itching
• Rarely, drug-caused lung swelling or liver upset

Good to know:

Most people who take it for a short time have no trouble. The main risk comes from the licorice root (kanzo) in the mix.

Licorice can cause pseudoaldosteronism (a state where the body acts as if it has too much aldosterone, the hormone that makes you hold salt). This shows up as low potassium, held-on salt and water, and higher blood pressure. Rarely it leads to rhabdomyolysis (severe muscle breakdown that can damage the kidneys).

Risk goes up with a bigger dose, longer use and older age. It also goes up if you take water pills. These effects are documented in people, so they are not a theoretical worry.

How much Soshikokito should you take?

• Recommended daily: A common adult dose of the granule extract is 7.5 g a day. It is split into two or three doses. Doses differ by brand and by person. Follow the label or the dose your prescriber sets. Children should only take it under a doctor's care.
• Best time of day: It is usually taken two or three times a day, spread across the day. Doses are often timed before meals.
• With or without food: Kampo granules are usually taken on an empty stomach, about 30 minutes before a meal, or between meals. Warm water helps them dissolve. If it upsets your stomach, take it with food instead.
• Time to effect: Some people notice easier breathing within a few days. Others feel nothing after two to four weeks. If nothing changes by then, it is unlikely to help you.
• How long to take it: Short courses are safer than long ones. Many practitioners review progress after two to four weeks. If you see no change by then, stop and rethink. If you use it for more than a few weeks, ask your doctor to check your blood pressure and your blood potassium.