Stomach Problems in Japan: How to Find the Right Japanese OTC Meds at the Drugstore

When your stomach feels heavy or indigestion sets in, what do you reach for? We all have our go-to choices for over-the-counter medication, but when you’re indulging in rich bowls of ramen and marbled wagyu in Japan and your stomach feels a little off, the options at the nearest Japanese drugstore are probably different from what you’re used to. With so many different options, it’s hard to know what to buy.

So what do locals choose?  In Japan, one of the most popular brands of stomach medicine is Ohta’s Isan, big enough that most people know of it even if they’ve never taken anything for their stomach before. Even within Japan, however, many people think that Ohta’s Isan is just one product. In reality, the brand makes a variety of different over-the-counter medications for your whole digestive system, designed for different needs. To help you find what you’re looking for at the drug store while you’re in Japan, we’ve summarized the details of four Ohta’s Isan recommendations.

① Ohta’s Isan S

When It’s Used: After a huge meal or a night of drinking, or as a general digestive aid.

^{→ Indications: Overconsumption of alcohol, heartburn, stomachache, indigestion, overfullness, poor appetite, hyperacidity, bloating, heaviness in the chest or stomach, vomiting, belching, nausea, weak stomach.)}

What It’s Known For: The Ohta’s Isan company has been engaged in medical research for over 145 years, and much of that time has been spent on natural ingredients, many of which they still utilize today. Ohta’s Isan S includes a blend of naturally derived ingredients to help calm your stomach even after consuming a little too much food or alcohol for comfort.

To help your stomach out even when it’s worse for wear, the formula includes seven herbal ingredients, including some surprisingly familiar remedies (cinnamon, fennel, nutmeg, clove, citrus peel, gentian, and Indian quassia). You’ll also find antacids and digestive enzymes on the ingredient list, to neutralize excess stomach acid while promoting digestion.

Ohta’s Isan S actually comes as a loose powder, which is offered in two types of packaging. If you go for standard Ohta’s Isan S you’ll get a can with a small scoop to help you measure your dose, as well as an inner lid to even out each scoop. A good option for at-home use.

Boxes labeled Ohta’s Isan <Sachet> S are full of small packets (or “sachets”), each of which contains a full adult dose of the medication—convenient for keeping with you on the go. Whichever you choose, the medicine is the same—just dump the powder in your mouth and swallow for a refreshing feeling. The powder is specially manufactured to take advantage of all the herbal aromas, with added l-menthol for a cooling sensation.

Ohta’s Isan S / Ohta’s Isan <Sachet> S (太田胃散Ｓ/太田胃散＜分包＞S)
“Ohta’s Isan S” Dosage:
　Adults (15+): 1.3g per dose
　Children (8-14): 0.65g per dose
Ohta’s Isan <Sachet> S Dosage:
　Adults (15+): 1 packet per dose
　Children (8-14): 1/2 packet per dose
*Not for children under 8.
Directions: Take with water (cold or lukewarm) after or between meals (including bedtime).
Product Page (en)

② Ohta’s Isan A <Tablet>

When It’s Used: When you’ve had a greasy meal or overeaten and heartburn is setting in, or when you have no appetite at all.

^{→ Indications: Indigestion, overfullness, stomachache, heartburn, poor appetite, hyperacidity, heaviness in the chest or stomach, vomiting, belching, nausea, weak stomach.}

What It’s Known For: This classic Japanese gastrointestinal pill has a formula that utilizes four ingredients to promote digestion: lipases AP6, ursodeoxycholic acid, prozyme 6, biodiastase 1000. These enzymes and acids help your body to quickly and efficiently process fats, proteins, and carbohydrates. When your digestive system is having a hard time, these ingredients help things along. That means you can enjoy that big platter of karaage fried chicken without worrying about stomach issues.

Ohta’s Isan A <Tablet> comes in bottles, but you can also get boxes where the medicine is divided into slim packets containing 3 tablets, which fit nicely into the pockets of your everyday bag. Convenient!

Ohta’s Isan A <Tablet> (太田胃散Ａ＜錠剤＞)
Dosage:
　Adults (15+): 3 tablets per dose
　Children (8-14): 2 tablets per dose
　Children (5-7): 1 tablet per dose
*Not for children under 5.
Directions: Take with water (cold or lukewarm) between meals (including bedtime).
Product Page (en)

③ Ohta’s Isan Seichoyaku

When It’s Used: To help regulate your intestinal environment, especially when stress or alcohol leaves your digestive system feeling especially sensitive.

^{→ Indications: Loose stool, constipation, bloating, general intestinal regulation.}

What It’s Known For: Designed to support the digestive systems of those with weak or sensitive stomachs, these pills combine probiotics like lactic acid bacteria and herbal ingredients to help normalize the intestinal environment. The bifidobacterium longum and lactobacillus gasseri (both lactic acid bacteria) work alongside clostridium butyricum to increase beneficial bacteria and suppress the growth of harmful bacteria, helping your intestines find a better balance.

The tablets also make use of two herbal ingredients, geranium and mallotus bark, which are especially helpful when it comes to keeping you regular—relieving both constipation and irritable bowels.

Ohta’s Isan Seichoyaku (太田胃散整腸薬)
Dosage:
　Adults (15+): 3 tablets per dose
　Children (8-14): 2 tablets per dose
　Children (5-7): 1 tablet per dose
*Not for children under 5.
Directions: Take 3 times a day after meals with water (cold or lukewarm).
Product Page (en)

④ Ohta Kampo Ichoyaku Ⅱ

When It’s Used: As a tool to improve persistent stomach pain or a weak stomach caused by stress or anxiety.

^{→ Indications: For individuals with gastrointestinal weakness, stomach or abdominal pain, nervous/chronic gastritis, or other autonomic nervous system imbalances sometimes accompanied by heartburn, belching, indigestion, loss of appetite, nausea, or vomiting.}

What It’s Known For: This medication relies on Japan’s traditional “kampo” medicinal system, utilizing traditional ingredients to address stomach issues caused by disturbances in your autonomic nervous system.

The autonomic nervous system regulates many of the basic processes in your body, including heart rate, blood pressure, and digestion, so when it’s thrown off balance by stress, anxiety, or tension, it can cause all kinds of digestive discomfort. The modern Ohta Kampo Ichoyaku Ⅱ includes a traditional kampo formula called Anchusan-ka-Bukuryo that’s believed to literally calm the nerves, helping to regulate the autonomic nervous system and stomach. Effects include neutralizing stomach acid, suppressing pain and spasms, and generally improving stomach function through its aroma.

Ohta Kampo Ichoyaku Ⅱ is often recommended for those suffering from stress due to work or family, as well as anyone with a weak digestive system, including people who suffer from stomach problems even when they haven’t overindulged in food or alcohol.

The standard Ohta Kampo Ichoyaku Ⅱ comes as granules, which come packaged in small packets. You can also find the medication in pill form as Ohta Kampo Ichoyaku Ⅱ <Tablet>, which also comes in small packets. Both versions of the medicine contain the same active ingredients, so people tend to choose whichever they feel more comfortable taking.

Ohta Kampo Ichoyaku Ⅱ / Ohta Kampo Ichoyaku Ⅱ <Tablet> (太田漢方胃腸薬Ⅱ/太田漢方胃腸薬Ⅱ＜錠剤＞)
Ohta Kampo Ichoyaku Ⅱ Granule Dosage:
　Adults (15+): 1 packet per dose
　Children (7-14): 2/3 packet per dose
Ohta Kampo Ichoyaku Ⅱ <Tablet> Dosage:
　Adults (15+): 3 tablets per dose
　Children (7-14): 2 tablets per dose
*Not for children under 7.
Directions: Take with water (cold or lukewarm) between meals (including bedtime), or on an empty stomach.
Product Page (en)

Tackle Digestive Discomfort in Japan, So You Can Get Back to Your Trip!

Digestive issues can derail a good meal—or a good trip—but knowing what to look for at a Japanese drugstore means you can take care of yourself during your trip to Japan, making all the difference. Whether you need fast relief after overindulging and giving yourself a stomach ache, daily support for a weak digestive system, or help improving stress-related stomach discomfort, these are just a few options to help you feel better. Plan a quick visit to the drugstore to look for the options that meet your body’s needs, and you’ll be ready to enjoy the rest of your busy itinerary, from deliciously greasy gyoza to the fattiest cuts of tuna!

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