What is Gorinsan?

Gorinsan is a herb mix used in Kampo, the herbal medicine of Japan. People take it for urinary problems. These include burning when you pass urine, going often, and cloudy urine.

It is one of the 148 Kampo formulas on Japan's approved list, set by the health ministry (MHLW). Doctors there can prescribe it. Elsewhere it is sold as a supplement.

Long use and proof of effect are two different things. Gorinsan has deep roots in Kampo. But almost no human trial evidence backs it, so treat the claims below with care.

How does Gorinsan work?

No one has shown how Gorinsan works in the body. What follows comes from tradition and lab work.

In Kampo terms, the mix is said to clear "heat" and "damp" from the lower body. In plain words, it is aimed at hot, painful, hard-to-pass urine.

Lab work points to a few herbs. Skullcap root and gardenia fruit calm swelling in cells and in animals. Plantain seed and water plantain make animals pass more urine.

These findings are early. They do not show that the whole mix helps a person with bladder pain.

What forms does Gorinsan come in?

Most Gorinsan comes as a dried extract in granules. Each sachet holds one dose. This is the standard form in Japan.

You may also see tablets, loose powder or capsules. Some Kampo practitioners boil the raw herbs into a tea.

Strength differs by maker. Check the label for the daily amount of extract. Buy from a firm that tests its herbs for heavy metals.

Where it comes from:

Gorinsan comes from a Chinese text of the Song dynasty, the Taiping Huimin Hejijufang, from about the 1100s. The name means "powder for the five kinds of painful urination".

Japanese doctors took the recipe into Kampo and kept using it. It has been a standard bladder formula there for centuries.

Today it sits on Japan's approved list of 148 Kampo formulas.

What does Gorinsan help with?

• Burning or stinging when you pass urine: This is the classic Kampo use for Gorinsan, and it is why the formula exists. Kampo doctors in Japan have used it this way for centuries. There are no good human trials that test it against a dummy pill, so we cannot say how well it works.
• Needing to pass urine often: Tradition places this squarely in Gorinsan's range. Two of the herbs make animals pass more urine, which is lab evidence, not proof in people. If you suddenly need to go far more often, get checked first.
• Cloudy urine: Kampo texts list cloudy or dark urine as a sign that fits this formula. Cloudy urine can also mean an infection or a kidney stone. See a doctor before you treat it yourself.
• Feeling that your bladder is not empty: Traditional use covers this, and it is often part of the picture Kampo doctors call "lin". No human trial has tested Gorinsan for it. In men, this feeling can also come from a large prostate, so it is worth a check-up.
• Repeat bladder infections (cystitis), used alongside proper medical care: In Japan it is sometimes given with, not instead of, standard care. Gorinsan is not an antibiotic (a germ-killing medicine) and will not clear an infection. An untreated bladder infection can move to the kidneys, which is serious.
• Mild irritation of the urethra (the tube urine passes through): Traditional use includes mild soreness with no fever. Evidence in people is missing. Pain with discharge needs testing for a sexually passed infection, not a herb.

Which foods are rich in Gorinsan?

1. Licorice sweets and licorice tea: they hold the same glycyrrhizin as the kanzo in this formula, so the amounts add up
2. Gardenia colouring (kuchinashi) in Japanese sweets and pickles — the same fruit used in the mix, though the food amount is tiny

What are the side effects of Gorinsan?

• Upset stomach, nausea or loss of appetite
• Loose stools or diarrhoea
• Rash or itching
• Swelling in the face, hands or ankles
• A rise in blood pressure
• Muscle weakness, cramps or an odd heartbeat from low potassium (a salt your heart and muscles need)
• Rare liver injury, with yellow skin, dark urine or deep tiredness
• Rare lung inflammation, with a dry cough, fever and breathlessness
• Belly pain and bloating after long use, from hardened veins in the bowel

Good to know:

Most people who take Gorinsan for a short time have no trouble. Mild stomach upset is the most common complaint.

The serious effects are rare but real, and they are the reason this is not a routine-tier herb. Licorice root can raise blood pressure and drop your potassium. Skullcap root has been linked, rarely, to liver injury and lung inflammation in Japanese safety reports.

Older people, and anyone on a water pill, are more likely to run into the potassium problem.

How much Gorinsan should you take?

• Recommended daily: In Japan, the usual prescribed amount is 7.5 g of dried extract granules a day, split into two or three doses. Products differ, so follow the label on your own pack. No safe amount has been set for children, and no standard dose exists outside Japan.
• Best time of day: Spread the doses through the day, two or three times, at even gaps.
• With or without food: Japanese practice is to take it on an empty stomach, before or between meals. If it upsets your stomach, take it with food instead.
• Time to effect: Kampo practice expects some change within a few days for sudden symptoms. This is based on custom, not trial data. No effect after about a week means it is time to stop and get checked.
• How long to take it: Short courses only. If your symptoms have not eased within about one week, stop and see a doctor. Do not take it month after month with no review. Long daily use of gardenia-containing formulas has been tied to bowel damage. If you use it on and off for more than a few months, ask your doctor to check your blood pressure and potassium.