You are halfway through your Senso-ji temple visit in Asakusa when your vision blurs and nausea hits you like a wall. The sweat is pouring — or maybe it has stopped completely. Your head is pounding, your legs feel heavy, and you cannot think straight. It is 34°C in the shade, and the humidity makes it feel like 42°C. You check your phone — the nearest hospital does not have English-speaking doctors. Sound familiar? You are not alone. Heat-related illness is the number one health emergency for tourists visiting Tokyo in summer, and knowing what to do right now could save your trip — or your life.
\n\n\n\n\n\n\n\n
Why Tokyo’s Summer Is Dangerous for Tourists
\n\n\n\nTokyo’s summer is not just hot — it is oppressively humid, and that combination is what makes it genuinely dangerous. From late June through September, temperatures regularly exceed 35°C (95°F) with humidity levels above 80%. The “feels like” temperature frequently climbs past 40°C (104°F), making it harder for your body to cool down through sweating.
\n\n\n\n- \n
- Extreme heat + humidity: When humidity is this high, your sweat cannot evaporate efficiently. Your body’s natural cooling system simply stops working the way it should. \n\n\n\n
- 57% of foreign visitors report heat-related symptoms: According to a Japan Meteorological Agency survey, more than half of tourists visiting Japan in summer experience some form of heat illness — from mild dizziness to full heat stroke. \n\n\n\n
- Long outdoor sightseeing: Walking between temples, shrines, and markets in direct sunlight — often for hours without a break — dramatically increases your risk. \n\n\n\n
- Alcohol and dehydration: A cold beer at an izakaya the night before feels refreshing, but alcohol is a diuretic. If you did not rehydrate properly, you start the next day already depleted. \n\n\n\n
- Jet lag and sleep deprivation: Fatigue weakens your body’s ability to regulate temperature. Combine that with an unfamiliar climate, and you have a recipe for trouble. \n\n\n\n
- Summer festivals and fireworks: Events like Sumida River Fireworks or local matsuri often require standing outdoors for hours in packed crowds with no shade. These are peak heat illness situations. \n
What You Can Do Right Now — First Aid for Heat Stroke
\n\n\n\nIf you or someone in your group is showing signs of heat illness, act immediately. Do not wait to “see if it gets better.” The faster you cool down, the lower the risk of serious complications.
\n\n\n\nGet Out of the Heat Immediately
\n\n\n\nMove to an air-conditioned space right away. In Tokyo, you are never far from one. The nearest convenience store (7-Eleven, Lawson, FamilyMart), department store, or train station all have powerful air conditioning. Even stepping into a subway entrance will drop the temperature significantly.
\n\n\n\nRehydrate with Electrolytes — Not Just Water
\n\n\n\nPlain water alone is not enough. You need electrolytes and sodium to replace what you have lost through sweat. Head to any convenience store and look for these:
\n\n\n\n- \n
- OS-1 (オーエスワン) — A medical-grade oral rehydration solution. This is the gold standard in Japan for dehydration. Available at pharmacies and some convenience stores. \n\n\n\n
- Pocari Sweat (ポカリスエット) — Japan’s most popular sports drink with balanced electrolytes. Available everywhere. \n\n\n\n
- Aquarius (アクエリアス) — Another reliable electrolyte drink found in every convenience store and vending machine. \n\n\n\n
- Enbun Charge tablets (塩分チャージ) — Salt and electrolyte tablets. Small, portable, and easy to carry in your bag. Grab a pack from any convenience store or drugstore. \n
Pro tip: Japan has vending machines on nearly every street corner. If you cannot find a convenience store, look for the nearest jidohanbaiki (自動販売機) — cold drinks are always just a few steps away.
\n\n\n\nCool Your Body Down Fast
\n\n\n\nTarget the three key cooling points on your body where blood vessels are closest to the skin: the sides of your neck, your armpits, and your groin area. Apply cold water bottles, ice packs, or wet towels to these areas. At Japanese drugstores, you can find Netsusama Sheet (熱さまシート) — cooling gel patches that stick to your skin and provide instant relief.
\n\n\n\nWhat NOT to Do
\n\n\n\n- \n
- Do not push through it. “Just one more temple” thinking is how mild heat exhaustion becomes a medical emergency. \n\n\n\n
- Do not drink beer or alcohol to “cool down.” Alcohol accelerates dehydration. It makes everything worse. \n\n\n\n
- Do not ignore early symptoms. Dizziness, nausea, and muscle cramps are your body’s warning signals. Listen to them. \n
When to See a Doctor — Know the Severity Levels
\n\n\n\nNot all heat illness is the same. Here is how to assess your situation and decide what to do next.
\n\n\n\nMild — Heat Exhaustion (Self-Care May Be Enough)
\n\n\n\n- \n
- Dizziness or lightheadedness \n\n\n\n
- Heavy sweating \n\n\n\n
- Mild headache \n\n\n\n
- Slight nausea \n
What to do: Move to a cool place, drink electrolytes, rest. If symptoms improve within 20–30 minutes, you can continue your day — but take it easy and stay hydrated.
\n\nModerate — Come to Our Clinic
\n\n\n\n- \n
- Symptoms persist for more than 30 minutes despite resting in a cool place \n\n\n\n
- Vomiting or inability to keep fluids down \n\n\n\n
- Body temperature above 38°C (100.4°F) \n\n\n\n
- Muscle cramps or spasms (especially in legs) \n\n\n\n
- Extreme fatigue or weakness \n\n\n\n
- Cannot drink water or electrolytes without vomiting \n
What to do: You need medical attention. Come to our clinic — we can provide IV fluid rehydration, cooling treatment, and monitor your condition in English.
\n\nSevere — Call Us (Emergency)
\n\n\n\n- \n
- Confusion, disorientation, or loss of consciousness \n\n\n\n
- Skin is hot and dry — sweating has stopped (this means your body’s cooling system has failed) \n\n\n\n
- Body temperature above 40°C (104°F) \n\n\n\n
- Seizures or convulsions \n\n\n\n
- Rapid heartbeat with shallow breathing \n
What to do: This is a life-threatening emergency. call us (Japan’s emergency number) immediately. While waiting for the ambulance, move the person to shade, remove excess clothing, and apply cold water or ice to the neck, armpits, and groin. If they are conscious, give small sips of water.
\n\n\n\n\n\n
What Happens at Our Clinic — 4 Simple Steps
\n\n\n\nIf you come to SAKURA International Clinic Asakusa with heat-related symptoms, here is exactly what to expect. Everything is handled in English from start to finish.
\n\n\n\nStep 1: Walk In or WhatsApp Us
\n\n\n\nNo appointment needed. Walk in during our opening hours, or send us a message on WhatsApp to let us know you are on the way. We are 1 minute on foot from Asakusa Station. If you are too unwell to walk, message us your location and we can advise you on the fastest way to reach us.
\n\n\n\nStep 2: Assessment and Cooling
\n\n\n\nOur English-speaking doctor will check your vital signs — body temperature, blood pressure, heart rate, and oxygen levels. We will assess the severity of your heat illness and begin cooling treatment immediately if needed.
\n\n\n\nStep 3: IV Fluid Rehydration (If Needed)
\n\n\n\nIf you are moderately dehydrated or unable to keep fluids down, we will start an IV drip with saline and electrolytes. This is the fastest and most effective way to rehydrate your body — most patients feel significantly better within 30 to 60 minutes. We also provide oral rehydration solutions and monitor your temperature throughout.
\n\n\n\nStep 4: Recovery Plan and Documentation
\n\n\n\nBefore you leave, the doctor will give you clear recovery instructions — how much to drink, what activities to avoid, and when to seek further help. We provide an English medical certificate documenting your visit and diagnosis. If your condition requires further treatment at a hospital, we will write a referral letter and help coordinate the transfer.
\n\n\n\n\n\n\n\n
Travel Insurance and Heat Stroke
\n\n\n\nHeat stroke and dehydration are covered by most international travel insurance policies as an acute medical condition. Here is what you need to know:
\n\n\n\n- \n
- We provide all necessary documentation — English medical certificate, itemized receipt, and diagnosis report — that insurance companies typically require for reimbursement. \n\n\n\n
- Contact your insurer first if possible. Many policies require you to notify them within 24 hours of seeking treatment. Check your policy documents or app before your visit. \n\n\n\n
- We accept upfront payment. Most travel clinics in Japan require you to pay at the time of service and claim reimbursement from your insurer afterward. We accept Visa, Mastercard, AMEX, JCB, and cash. \n\n\n\n
- Keep all receipts. We provide clearly itemized receipts in English to make the claims process as smooth as possible. \n
\n\n\n\n
How to Survive Tokyo’s Summer — A Practical Guide for Tourists
\n\n\n\nPrevention is always better than treatment. If you are visiting Tokyo between June and September, these tips could be the difference between a great trip and a medical emergency.
\n\n\n\nPlan Around the Danger Hours
\n\n\n\nThe most dangerous period is 11:00 AM to 3:00 PM, when UV radiation and temperature peak. Schedule outdoor sightseeing — temples, shrines, gardens — for the early morning (before 10 AM) or late afternoon (after 4 PM). Reserve the midday hours for indoor attractions: museums, aquariums, department stores, or a long lunch in an air-conditioned restaurant.
\n\n\n\nDress for the Heat
\n\n\n\nWear a hat and use a parasol (higasa, 日傘). In Japan, parasols are used by everyone — men included — and it is one of the most effective ways to reduce heat exposure. Choose lightweight, breathable, light-colored clothing. Avoid dark colors that absorb heat.
\n\n\n\nDrink Before You Are Thirsty
\n\n\n\nBy the time you feel thirsty, you are already mildly dehydrated. Aim for at least one cup (200–250 ml) of water or electrolyte drink every hour you are outside. Carry a reusable bottle and refill at convenience stores or from vending machines.
\n\n\n\nCheck the WBGT Heat Index
\n\n\n\nJapan’s Ministry of the Environment publishes a Wet Bulb Globe Temperature (WBGT) index — a more accurate measure of heat danger than temperature alone because it accounts for humidity, wind, and sun exposure. Check the Heat Stroke Prevention Information site (available in English) each morning before heading out. If the WBGT is 28 or above, limit outdoor time.
\n\n\n\nUse Tokyo’s “Cooling Spots”
\n\n\n\nTokyo is full of naturally air-conditioned spaces. Convenience stores are everywhere and always cold. Department store basements (depachika) are cool and offer amazing food. Subway stations and underground passages stay comfortable even on the hottest days. Plan your route so you can duck into these spots every 20–30 minutes.
\n\n\n\nPick Up Cooling Goods at a Drugstore
\n\n\n\nJapanese drugstores sell an incredible range of summer cooling products. Look for handy fans (ハンディファン), cooling towels (冷感タオル), cooling body sprays, and Netsusama Sheets (熱さまシート). These are inexpensive, widely available, and genuinely effective. Stores like Matsumoto Kiyoshi, Sundrug, and Welcia are on almost every major street in Tokyo.
\n\n\n\n\n\n\n\n
Frequently Asked Questions
\n\n\n\nWhat is the difference between heat exhaustion and heat stroke?
\nHeat exhaustion is the earlier, less severe stage. Symptoms include heavy sweating, dizziness, nausea, headache, and muscle cramps. Your body is still trying to cool itself down. Heat stroke is the severe, life-threatening stage that occurs when your body’s temperature regulation fails completely. Key signs: body temperature above 40°C, confusion or loss of consciousness, and — critically — your skin becomes hot and dry because sweating has stopped. Heat exhaustion can progress to heat stroke quickly if not treated, which is why early intervention is so important.
\nAre children and elderly travelers at higher risk?
\nYes, significantly. Children are closer to the ground (where reflected heat is strongest), have a higher surface-area-to-body-weight ratio, and may not recognize or communicate symptoms early. Elderly travelers have reduced ability to regulate body temperature, may take medications that affect sweating (such as diuretics or beta-blockers), and are more likely to become dehydrated. If you are traveling with children or elderly family members, take extra precautions: limit outdoor time during peak hours, ensure frequent hydration, and seek medical attention at the first sign of trouble.
\nCan I just go back to my hotel and rest?
\nFor mild heat exhaustion — if you feel dizzy or have a mild headache but symptoms improve within 20–30 minutes of resting in a cool place with fluids — yes, returning to your hotel to rest is reasonable. However, if you are vomiting, cannot keep fluids down, have a temperature above 38°C, or your symptoms are not improving, you should see a doctor. Moderate heat illness can worsen rapidly, and IV rehydration at a clinic is far more effective than trying to drink your way back to normal when your body is already struggling to absorb fluids.
\nDoes travel insurance cover heat stroke treatment?
\nIn most cases, yes. Heat stroke and dehydration are classified as acute medical conditions, and the vast majority of international travel insurance policies cover emergency medical treatment for these conditions. We provide English-language medical certificates, itemized receipts, and diagnosis reports — everything your insurance company will need for reimbursement. We recommend checking your specific policy and notifying your insurer within 24 hours of treatment.
\nHow much does a visit cost?
\nOur all-inclusive fee is ¥55,000 (tax included). This covers the doctor consultation, assessment, IV fluid rehydration (if needed), cooling treatment, medication, and an English medical certificate. If you need a referral letter to a hospital or specialist, the additional cost is ¥11,000. There are no hidden fees. We accept Visa, Mastercard, AMEX, JCB, and cash.
\n\n\n\n\n\n\n
Feeling the Heat? Do Not Wait — Get Help Now.
\n\n\n\nHeat illness gets worse fast. Walk in or message us on WhatsApp — no appointment needed.
\n\n\n\n\n\n\n\nSAKURA International Clinic Asakusa
1 min walk from Asakusa Station · 7F
Open every day 9:00 AM – 5:00 PM (including weekends & holidays)
Languages: English · 中文 · 한국어 · 日本語
\n\n\n\n
Related Pages
\n\n\n\n- \n
- Fever in Tokyo – What to Do \n\n\n\n
- Stomach Pain & Diarrhea in Tokyo \n\n\n\n
- Allergy Symptoms in Tokyo \n\n\n\n
- Health Guide: Sick in Tokyo? \n