Insect Bite / Sting in Japan: What to do (and when to call 119)
Last updated: 2025-03-06
A mosquito bite is a small nuisance. A wasp sting can be a warning bell. And in Japan’s rainy season, even the forest floor can reach for you—yamabiru (land leeches) love the humid months.
General information, not medical advice. If you think it could be serious, treat it as urgent.
TL;DR (30-second decision)
- Call 119 now if there’s trouble breathing, throat tightness, swelling of lips/tongue/face, widespread hives, fainting, severe dizziness, or rapid worsening after a sting/bite (possible anaphylaxis).
- Go to a clinic the same day if:
- a tick is attached (don’t yank it),
- swelling/pain keeps worsening, or you suspect infection (spreading redness, pus, fever).
- For mild bites/stings: remove stinger (if present), wash, cool, and use OTC anti-itch options.
- Japan tip: OTC insect repellent and anti-itch creams are easy to buy at drugstores/pharmacies. Repellent ingredients you’ll see: DEET (ディート) or icaridin/picaridin (イカリジン).
Call 119 immediately (red flags)
Call an ambulance right away if any of these happen after a bite/sting:
- Trouble breathing / wheezing / “can’t get air”
- Swelling of lips, tongue, throat, face
- Widespread hives (not just around the bite), flushing
- Fainting, confusion, severe dizziness
- Repeated vomiting + feeling unwell
- Sting/bite inside the mouth/throat (swelling can block the airway)
- You have a known severe allergy (or carry an epinephrine auto-injector)
These are classic emergency signs of anaphylaxis—don’t “wait and see.”
Not sure, but stable?
If symptoms are mild and you’re stable, #7119 (if available in your area) can advise whether you need an ambulance and where to go.
What to do right now (safe first aid)
1) Get to safety + prevent swelling traps
- Move away from the insect/nest (avoid “second sting”).
- Remove rings/watches near the area before swelling increases.
2) If there’s a stinger (bee stings)
- Scrape it out (fingernail / blunt edge / card). Don’t squeeze it.
Note: wasps typically don’t leave a stinger.
3) Wash + cool
- Wash with soap and water.
- Apply a cold pack (10–20 minutes, repeat).
4) Itch control (simple, low-risk)
- Calamine lotion or 0.5–1% hydrocortisone cream can reduce itch/inflammation.
- Don’t scratch if you can help it—scratching is how “minor” becomes infected. (Yes, I know that’s a cruel thing to say when it’s itchy.)
Japan-specific “watch-outs” (this is where people mess up)
A) Tick bite (マダニ): don’t pull it off
If a tick is attached and feeding, don’t forcibly remove it—mouthparts can remain and the site can become problematic. Go to a clinic for proper removal.
Also: ticks can transmit infections, so prevention (covered skin + repellent) matters.
B) Rainy season = yamabiru (land leeches) season
In parts of Japan, yamabiru activity increases from spring to autumn, and it becomes especially active during the rainy season (June–July) and after rain.
If one attaches:
- Official guidance notes you can remove it, and methods like salt (or heat) can help it detach.
- After removal: clean, cover the wound, and watch for infection symptoms.
Prevention (the boring stuff that saves your ankles):
- long socks + tuck pants into socks
- avoid brushing bare legs against wet grass/leaf litter
- apply repellent to shoes/socks as well
What to buy in Japan (OTC): insect repellent + anti-itch
Insect repellent (虫よけ / 虫よけスプレー)
Common active ingredients:
- DEET (ディート)
- MHLW guidance includes child-use limits (e.g., not for infants under 6 months; limited applications for young children; avoid face).
- Icaridin / Picaridin (イカリジン)
- Japanese guidance notes no specific age restriction (unlike DEET).
Duration (practical rule of thumb): Japan’s MHLW notice shows typical “effective time” ranges by concentration (e.g., DEET 10–12% ≈ 3–5h; 30% ≈ 5–8h; icaridin 15% ≈ 6–8h).
Sunscreen + repellent order: apply sunscreen first, then repellent (Japanese guidance notes repellent over sunscreen can shorten repellent duration).
Anti-itch (かゆみ止め / 虫さされ)
Ask for something for:
- itch (かゆみ)
- swelling (腫れ)
- insect bite (虫さされ)
Options commonly used in first-aid guidance include calamine and low-strength hydrocortisone.
(Products vary by store; asking by goal works better than hunting a brand name.)
What to say (simple English + Japanese keywords)
At a pharmacy/drugstore
“I have an insect bite / sting. It’s very itchy and swollen.
Do you have something for itching and swelling?”
Japanese keywords: 虫さされ (mushisare), かゆみ止め (kayumidome), 腫れ (hare)
If you need repellent:
“I need insect repellent. Is this DEET or icaridin?”
Japanese keywords: 虫よけ (mushiyoke), ディート (DEET), イカリジン (icaridin)
If calling #7119 (if available)
“I was bitten/stung.
Symptoms: [hives / swelling / pain / dizziness].
Do I need an ambulance? Where should I go?”
If calling 119 (emergency)
Start with: “Medical emergency.” Then location + symptoms.
When you should see a doctor soon (same day / within 24 hours)
- Tick attached, or you suspect tick bite with worsening symptoms
- Rapidly expanding redness, pus, fever (possible infection)
- Bite/sting near the eye, inside the mouth, or severe facial swelling
- Symptoms last more than a few days and keep worsening
FAQ
1) “It’s just a bite.” When is it not “just a bite”?
When it becomes systemic: breathing trouble, throat swelling, widespread hives, fainting—treat as emergency (anaphylaxis).
2) Do bees and wasps differ?
Yes—bees may leave a stinger; many wasps can sting repeatedly. Remove any visible stinger by scraping it out.
3) Can I buy insect repellent in Japan?
Yes. You’ll commonly see DEET or icaridin products. MHLW guidance includes child-use cautions for DEET, and effectiveness-duration labeling by concentration.
4) Why are leeches such a rainy-season problem?
In some areas, yamabiru activity increases during warm, wet periods, especially rainy season and after rain.
5) I found a tick attached—should I pull it out?
Don’t force it out. Guidance warns mouthparts can remain; seek proper treatment/removal.