Is This You?
\n\n\n\nYou tried that incredible sashimi platter last night in Shinjuku — or maybe it was the yakitori from a street stall near Shibuya. Either way, you woke up at 3 AM with your stomach in knots. Now it’s morning, and instead of exploring Senso-ji Temple or browsing Tsukiji Outer Market, you’re stuck in your hotel bathroom with waves of nausea, cramping, and diarrhea. You’re worried about dehydration, unsure what medicine to buy, and you have no idea how to see a doctor who speaks English. Sound familiar? You’re not alone — and we can help.
\n\n\n\nCommon Causes of Stomach Problems for Tourists in Japan
\n\n\n\nStomach pain, diarrhea, and vomiting during a Japan trip can have several causes. Understanding what might be behind your symptoms helps you decide whether to wait it out or seek medical care right away.
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- Food poisoning from raw fish (sushi & sashimi) — Japan’s food safety standards are among the world’s highest, but raw seafood always carries some risk, especially for visitors whose bodies aren’t accustomed to it. \n\n\n\n
- Anisakis (parasitic infection) — A parasite found in raw fish that causes sudden, intense stomach pain within hours of eating sashimi or sushi. Japan reports over 7,000 cases per year, making it a uniquely Japanese health risk for tourists. \n\n\n\n
- Norovirus — Highly contagious and especially common during winter months (November–February). Causes explosive vomiting and watery diarrhea. \n\n\n\n
- Campylobacter — Often caused by undercooked chicken, including dishes like chicken sashimi (torisashi) served at some izakaya restaurants. \n\n\n\n
- Traveler’s diarrhea — Even in a clean country like Japan, changes in diet, water mineral content, and unfamiliar ingredients can upset your digestive system. \n\n\n\n
- Overeating and drinking — Between all-you-can-eat yakiniku, conveyor-belt sushi, ramen crawls, and izakaya hopping, it’s easy to overdo it on vacation. \n\n\n\n
- Stress-related gastritis — Jet lag, packed itineraries, and travel anxiety can trigger stomach inflammation even without a food-related cause. \n
What You Can Do Right Now: First Aid for Stomach Trouble in Japan
\n\n\n\nBefore heading to a clinic, there are steps you can take to manage mild symptoms on your own. The most important thing is preventing dehydration.
\n\n\n\nRehydrate immediately
\n\n\n\nHead to any convenience store (7-Eleven, FamilyMart, Lawson) and pick up OS-1 (オーエスワン), a medical-grade oral rehydration solution, or Pocari Sweat (ポカリスエット), an electrolyte drink. Sip slowly and frequently — don’t gulp large amounts at once.
\n\n\n\nOver-the-counter medicines at Japanese pharmacies
\n\n\n\nJapanese pharmacies (kusuri-ya / 薬局) carry effective OTC options. Show the Japanese name on your phone to the pharmacist:
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- Probiotics / intestinal regulators: Biofermin (ビオフェルミン) or Seirogan (正露丸) — helps restore gut balance \n\n\n\n
- Anti-diarrheal: Stoppa (ストッパ) — fast-dissolving tablet for urgent relief \n\n\n\n
- Stomach acid / heartburn: Gaster 10 (ガスター10) or Ohta’s Isan (太田胃散) — for acid reflux and indigestion \n\n\n\n
- Anti-nausea: Travelmin (トラベルミン) — originally for motion sickness but effective for general nausea \n
Important caution: Anti-diarrheal medicines like Stoppa can actually be harmful if you have a bacterial infection, because they prevent your body from flushing out the pathogen. If you suspect food poisoning (especially after eating raw fish or undercooked meat), it’s better to let the diarrhea run its course and focus on rehydration until you can see a doctor.
\n\n\n\nWhen to See a Doctor — and When to Call Us
\n\n\n\nNot every upset stomach requires a clinic visit, but some symptoms should not be ignored. Here’s how to assess your situation:
\n\n\n\nMild — OK to monitor at your hotel
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- Mild diarrhea (1–2 loose stools) without other symptoms \n\n\n\n
- Slight stomach discomfort or bloating after a heavy meal \n
Moderate — Come see us at SAKURA International Clinic
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- Diarrhea or vomiting lasting more than 24 hours \n\n\n\n
- Blood in your stool or vomit \n\n\n\n
- Severe abdominal pain, especially after eating raw fish — this could be anisakis and requires prompt treatment \n\n\n\n
- Fever of 38°C (100.4°F) or higher along with gastrointestinal symptoms \n\n\n\n
- Unable to keep any fluids down \n\n\n\n
- Symptoms severe enough that you can’t continue your trip \n
Severe — Call Us (Japan’s emergency number) immediately
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- Confusion, dizziness, or feeling faint \n\n\n\n
- Signs of severe dehydration: no urination, extremely dry mouth, sunken eyes \n\n\n\n
- Uncontrollable vomiting that won’t stop \n
When calling 119, say “Kyukyusha onegaishimasu” (救急車お願いします) to request an ambulance. If you cannot speak Japanese, say “English please” — many dispatch centers now have interpreter support.
\n\nWhat to Expect at Our Clinic
\n\n\n\nIf your symptoms fall in the moderate category, here’s how your visit to SAKURA International Clinic Asakusa will go:
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- Contact us via WhatsApp or phone — Message us on WhatsApp to let us know you’re coming. Walk-ins are also welcome, but a quick message helps us prepare. \n\n\n\n
- Visit our clinic (1-minute walk from Asakusa Station) — We’re open every day of the year, 9:00 AM–5:00 PM. No referral needed. \n\n\n\n
- Consultation in English — Our doctor will take your full history, perform a physical examination, and order tests if needed (blood work, stool tests, etc.). The entire process typically takes 30–45 minutes. \n\n\n\n
- Treatment and prescriptions — Depending on your diagnosis, you may receive intestinal regulators, anti-nausea medication, antibiotics, IV fluids for dehydration, or a referral for endoscopy if anisakis is suspected. You’ll also get detailed guidance on managing symptoms for the rest of your trip. \n\n\n\n
- Documentation — We provide an English medical certificate and detailed receipts for your travel insurance claim. \n
Using Travel Insurance for Stomach Illness in Japan
\n\n\n\nMost travel insurance policies cover emergency medical treatment abroad, including food poisoning and gastrointestinal illness. Here’s what you need to know about using your insurance at our clinic:
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- We issue English-language medical certificates and itemized receipts — These documents contain the diagnosis codes and treatment details that insurance companies require for reimbursement. \n\n\n\n
- Payment process: You pay the full amount at the time of your visit, then submit a claim to your insurance provider after returning home. This is standard practice at most clinics in Japan. \n\n\n\n
- Cost without insurance: A standard consultation including examination, prescription, medical certificate, and basic tests/procedures is ¥55,000 (tax included). If you need a referral letter to another hospital, an additional ¥11,000 applies. \n\n\n\n
- We accept credit cards — Visa, Mastercard, and other major cards are accepted. \n
Tip: Before your trip, save a digital copy of your insurance policy and the emergency claims phone number on your phone. This makes the process much smoother if you do need medical care.
\n\n\n\nJapanese Food Culture and Stomach Trouble: What Every Tourist Should Know
\n\n\n\nJapan is a food lover’s paradise, and one of the few countries in the world where eating raw food is deeply embedded in everyday dining culture. The safety standards for raw fish, raw eggs, and other fresh ingredients in Japan are exceptionally strict — far more rigorous than in most other countries. However, no system is perfect, and there are some Japan-specific risks that visitors should understand.
\n\n\n\nAnisakis: Japan’s most common food-borne parasite
\n\n\n\nAnisakis is a parasitic worm found in raw marine fish, including salmon, mackerel, squid, and sardines. When you eat infected sashimi or sushi, the larvae can burrow into your stomach lining, causing sudden and severe abdominal pain — often within 2–8 hours of eating. Japan reports over 7,000 anisakis cases annually, making it the most common cause globally. The good news: it’s treatable. A doctor can remove the larvae via endoscopy, and the pain typically resolves immediately. If you experience intense stomach pain after eating raw fish, don’t wait — see a doctor right away.
\n\n\n\nRaw eggs: Lower risk than you might think
\n\n\n\nDishes like tamago kake gohan (raw egg on rice) and sukiyaki (dipping meat in raw egg) might seem alarming if you’re from a country where raw eggs are considered dangerous. In Japan, eggs are thoroughly washed and inspected, and salmonella rates are extremely low. That said, if you have a sensitive stomach or a weakened immune system, it’s perfectly fine to ask for your egg cooked.
\n\n\n\nChicken sashimi and rare liver
\n\n\n\nSome izakaya restaurants serve torisashi (chicken sashimi) or reba sashi (raw liver). While these are traditional delicacies, they carry a real risk of campylobacter infection, which causes diarrhea, fever, and abdominal cramps starting 2–5 days after exposure. If you’re not comfortable with the risk, it’s completely acceptable to decline.
\n\n\n\nFood allergies in Japan
\n\n\n\nJapan’s food labeling law requires manufacturers to declare seven major allergens: wheat, buckwheat, egg, milk, peanut, shrimp, and crab. However, restaurant menus don’t always list ingredients clearly, and many dish names give no hint about what’s inside. If you have food allergies, we strongly recommend carrying an allergy card (arerugi kaado) written in Japanese that lists your specific allergens. Several free templates are available online — print one before your trip or save it on your phone.
\n\n\n\nFrequently Asked Questions
\n\n\n\nHow can I tell if I have food poisoning or just an upset stomach?
\nFood poisoning typically comes with a combination of symptoms: diarrhea, vomiting, fever, and abdominal cramps, usually starting 2–12 hours after eating contaminated food. A simple upset stomach from overeating or stress tends to involve milder discomfort without fever or persistent vomiting. If your symptoms are severe, involve blood, or last more than 24 hours, it’s best to see a doctor rather than guessing — our clinic can run tests to determine the exact cause.
\nWhat happens if I have anisakis? What’s the treatment like?
\nIf anisakis is suspected based on your symptoms (intense stomach pain after eating raw fish), the standard treatment is an upper endoscopy (gastroscopy). The doctor uses a thin, flexible camera inserted through the mouth to locate and remove the anisakis larva with forceps. The procedure is quick — usually under 15 minutes — and pain relief is often immediate once the parasite is removed. Our clinic can assess your symptoms, provide initial care, and arrange an urgent referral for endoscopy at a nearby hospital if needed.
\nCan I fly with diarrhea? Is it safe to board my flight?
\nIn most cases, mild to moderate diarrhea won’t prevent you from flying, but it will be uncomfortable. Make sure to stay well-hydrated before and during the flight, sit near the aisle for easy bathroom access, and bring anti-diarrheal medication (after consulting a doctor). However, if you have severe dehydration, a high fever, or bloody stools, you should seek medical clearance before flying. We can provide a fit-to-fly assessment and medical certificate if your airline or insurance requires one.
\nIs Japan’s tap water safe to drink?
\nYes — Japan’s tap water is safe to drink throughout the country. It meets strict quality standards and is regularly tested. The water is soft (low mineral content), which is actually gentler on the stomach than hard water found in many European countries. If you’re experiencing stomach issues, tap water is not the likely cause. That said, some visitors with very sensitive stomachs may notice minor differences simply due to the change in water source and mineral composition — this is temporary and harmless.
\nHow much does a visit cost?
\nA standard consultation at SAKURA International Clinic Asakusa costs ¥55,000 (tax included). This covers the doctor’s consultation, physical examination, prescription, medical certificate, and basic tests or procedures. If you require a referral letter to a specialist or hospital, an additional ¥11,000 applies. We accept credit cards (Visa, Mastercard, and more). If you have travel insurance, we provide all the documentation you need to file a reimbursement claim.
\nGet Help Now — SAKURA International Clinic Asakusa
\n\n\n\nDon’t let stomach pain ruin your trip to Japan. Whether it’s food poisoning, anisakis, or traveler’s diarrhea, our English-speaking doctor can diagnose and treat you today.
\n\n\n\nSAKURA International Clinic Asakusa
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- Location: 1-minute walk from Asakusa Station \n\n\n\n
- Hours: 9:00 AM – 5:00 PM, open every day (365 days) \n\n\n\n
- Languages: English, Chinese, Korean, Japanese \n\n\n\n
- Cost: ¥55,000 (consultation, prescription, medical certificate, basic tests included / tax included) \n\n\n\n
- Referral letter: +¥11,000 \n\n\n\n
- Payment: Credit cards accepted \n
Related Pages
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- Fever, Cold & Flu in Tokyo — English-Speaking Clinic \n\n\n\n
- Allergies & Rash in Tokyo — English-Speaking Clinic \n