What is Siche?

Siche is the dried calyx of the persimmon — the woody, star-shaped cap that sits on top of the fruit of Diospyros kaki. In Korean herbal medicine it is used for one main job: stubborn hiccups. It is also given for belching and for a feeling of gas or pressure rising in the chest.

The honest verdict is that human trial evidence is thin. Most of what we know comes from long traditional use plus laboratory and animal work, so Siche is best understood as a traditional remedy rather than a proven treatment. Long use in a tradition is not proof that something works — that point applies to everything on this page.

It is almost always taken as a decoction (a tea made by simmering the dried herb in water), usually alongside clove and fresh ginger. Ordinary hiccups stop on their own within minutes or hours. Hiccups that drag on for more than two days are a medical problem, not a home-remedy problem.

How does Siche work?

Nobody has shown clearly how Siche works in people. The traditional explanation is that it settles "rebellious" stomach energy that pushes upward, which is how old Korean and Chinese texts describe hiccups and belching.

In modern terms, researchers have suggested it may act on the nerve loop that drives the diaphragm (the breathing muscle under your lungs) to spasm. That idea comes mostly from animal and test-tube work, not from trials in people.

Some laboratory studies report antioxidant and mild smooth-muscle-relaxing activity from persimmon extracts. Those findings are interesting but they do not tell you whether a cup of the tea will stop your hiccups.

What forms does Siche come in?

You will usually meet Siche in one of these forms:

Dried whole calyces, sold loose by weight for making a decoction. Cut or coarsely broken pieces for the same purpose. A ready-made granule or powdered extract dispensed by a Korean medicine practitioner, usually as part of a multi-herb formula.

Single-herb capsules exist but are uncommon. Persimmon leaf tea and persimmon fruit products are different things and are not substitutes for the calyx.

Where it comes from:

Siche has a long and consistent record across East Asia. It appears in Chinese materia medica from the Song period onward and was carried into Korean practice, where it is listed in the Dongui Bogam (1613) among remedies for hiccups and belching.

The best-known preparation is the classical clove-and-persimmon-calyx decoction, in which Siche is combined with clove and fresh ginger. Japanese Kampo practice uses the same pairing.

In Korean households, the calyx was also simply saved from eaten persimmons and dried for later use.

What does Siche help with?

• Hiccups, including hiccups that keep coming back: This is the main traditional use, and it is consistent across Korean, Chinese and Japanese texts. The modern evidence is weak. There are small, poorly reported case series from East Asia using multi-herb formulas that contain Siche, but no well-run trial of the calyx on its own that we can point you to. Most hiccups stop by themselves, which makes weak studies very hard to read. Hiccups lasting over 48 hours need a doctor's assessment.
• Belching and burping: Traditional texts group belching with hiccups and treat both with the same formulas. We found no human trials testing Siche for belching. Any benefit you notice is uncertain and could easily be the warm drink or the passage of time.
• A feeling of gas or pressure rising in the chest: In traditional terms this is the same pattern as hiccups — something pushing upward that should be settling downward. There is no clinical evidence for this use. If chest pressure comes with breathlessness, sweating or pain spreading to your arm or jaw, that is an emergency, not indigestion.
• Nausea linked to that rising feeling: Siche is usually combined with fresh ginger for this, and ginger is the better-studied partner of the two. There is no human evidence that Siche itself eases nausea. Treat this as traditional use only.

Which foods are rich in Siche?

1. Fresh persimmon fruit: the calyx is the cap on top of it, though the fruit flesh is not a substitute
2. Gotgam (Korean dried persimmon): often still carries the dried calyx
3. Persimmon leaf tea: a different part of the same plant, with different uses

Practical Tips:

Eating persimmon fruit does not give you the traditional remedy; the calyx is the part used.

What are the side effects of Siche?

• Dry, puckering mouth feel from the tannins
• Mild stomach upset or nausea
• Constipation
• Reduced absorption of iron from food or supplements
• Allergic reaction in people sensitive to persimmon (rash, itching, swelling)

Good to know:

Most people who drink a short course of the decoction have no trouble beyond a dry mouth. Reported problems are mild and settle when you stop.

The tannin load is the real issue. Heavy or prolonged use can worsen constipation and can lower how much iron your body takes in, which matters if you are already low in iron.

There is a rarer concern tied to persimmon generally: eating large amounts of unripe persimmon can form a bezoar (a hard lump of undigested plant material that can block the stomach or bowel). This is linked to the fruit rather than to normal doses of the calyx tea, but it is a reason not to take large amounts.

How much Siche should you take?

• Recommended daily: There is no modern tested dose. Korean and Chinese herbal texts commonly use about 5 to 10 g of the dried calyx a day, simmered in water as a decoction (a tea made by boiling the herb). Siche is rarely used alone. The classical formula pairs it with clove and fresh ginger, and a practitioner sets the amounts for the person in front of them. Do not raise the dose on your own. More tannin means more stomach upset and more interference with iron, not faster relief.
• Best time of day: Take it warm when symptoms are present. There is no evidence that a particular time of day works better.
• With or without food: It is usually taken warm after meals, since hiccups and belching often follow eating. Keep it at least two hours apart from any iron tablet.
• Time to effect: Traditional use expects relief within minutes to a few hours of drinking the decoction. This has not been measured in a proper trial, and many hiccups would have stopped anyway.
• How long to take it: Use it for the episode, not as a daily habit. A few days at most is the normal traditional pattern. If your hiccups have not settled after two days, stop self-treating and see a doctor. Long-running hiccups can be a sign of a problem in the stomach, the nerves or the brain.