Conjunctivitis — pink eye — is inflammation of the surface of the eye and the inside of the eyelid. It's common, usually settles on its own, and comes in three broad types: viral, bacterial, and allergic. They're treated differently, which is why the distinction matters.
What doesn't fit that picture is an eye that's genuinely painful, sensitive to light, or seeing less clearly. Those symptoms point away from ordinary conjunctivitis and need an eye specialist in person, not a video call.
Telling the three types apart
| Type | Typical picture |
|---|---|
| Viral | Watery discharge, often starts in one eye then affects the other, frequently alongside a cold. Very contagious. |
| Bacterial | Thicker, sticky discharge; lids may be gummed together in the morning. |
| Allergic | Both eyes, intense itching, often with sneezing or a runny nose. Common in pollen season. |
These overlap, and this table is a guide to likelihood rather than a diagnosis. If your symptoms coincide with pollen season, our hay fever guide covers the allergic side, which responds to entirely different treatment.
If you wear contact lenses
Take the lenses out and switch to glasses until the eye is completely normal again. Contact lens wearers are at higher risk of infections that involve the cornea rather than just the surface, and those are potentially sight-threatening — which is why a painful eye in a lens wearer is a same-day, in-person matter rather than something to watch overnight.
- Don't reuse the lenses or the case that were in use when symptoms started.
- Don't wear lenses again until the eye has been normal for a day or more.
- Bring your glasses on the trip. A pharmacy can't replace a prescription lens for you at short notice.
Not passing it on
Viral conjunctivitis spreads easily, and a hotel room shared with other people is an efficient way to do it. Wash your hands often, don't share towels or pillows, and avoid touching or rubbing the eye. Japanese hotels and ryokan often provide shared towels in a bathroom — use your own while symptoms last.
What an online consultation can do
A doctor can assess your symptoms, the pattern of discharge, whether one or both eyes are affected, and what else is going on, and decide what's appropriate — including a prescription where that's warranted. Photograph the eye in good light beforehand, and be ready to say whether vision has changed.
The limits are real and worth stating plainly. A video call cannot examine the eye with a slit lamp, measure pressure inside the eye, or stain the cornea to look for damage. Where any of that is needed — and it is, whenever there's pain, light sensitivity or reduced vision — the right answer is an eye clinic, and a doctor will send you there rather than prescribing.
Consultations run 9:00–18:00 JST, Monday to Saturday, in English with a Japan-licensed physician, and if a prescription is appropriate it's emailed to you and sent to a pharmacy near where you're staying.
Managing it on a trip
Conjunctivitis rarely stops a trip, but it does change a few things for a week. Glasses instead of lenses, sunglasses outdoors if light bothers you, and your own towel are the main adjustments.
- Use a separate towel and pillowcase from anyone you're sharing a room with, and wash your hands after touching your face.
- Skip onsen, public baths and pools until it's cleared. Shared water and an infectious eye are a poor combination, and most facilities ask that people who are unwell stay out.
- Clean discharge away from the inner corner outward with a clean tissue each time, and throw it away rather than reusing it.
- Don't share eye drops with anyone, and throw away any bottle that was in use when symptoms started.
- Replace eye makeup that was in use at the time; it can reinfect you afterward.
Why the type matters for treatment
The three types are not treated the same way, which is the practical reason not to buy the first eye drop you see. Allergic conjunctivitis responds to antihistamine treatment and is usually a pollen-season problem — in Japan, that means the cedar season our hay fever guide covers. Viral conjunctivitis mostly needs time and hygiene. Bacterial cases may need a prescription.
Using the wrong drop can prolong things, and one category in particular — steroid eye drops — can make certain infections considerably worse. That's not a decision to make from a shelf label in a language you don't read.
Where in-person care happens
Eye care in Japan is handled by 眼科 (ganka), the ophthalmology department, and clinics are common in most neighbourhoods and inside larger hospitals. That's where to go for any painful eye, any change in vision, an injury, or a contact lens wearer with symptoms — same day, not tomorrow.
How long does pink eye last?
Viral conjunctivitis often runs one to two weeks and clears on its own; bacterial cases typically settle faster once treated. Symptoms that worsen, or any pain or vision change, mean get seen rather than wait.
Can I get eye drops without a prescription in Japan?
Some eye drops are sold over the counter, but which drop is appropriate depends on the cause — and the wrong one can make certain conditions worse. Ask a pharmacist or a doctor first.
Can I keep wearing contact lenses?
No. Switch to glasses until the eye is completely normal, and don't reuse the lenses or case that were in use when it started.
When do I need an actual eye specialist?
Any significant pain, reduced or blurred vision, marked light sensitivity, an injury, or a painful eye in a contact lens wearer. Those need an in-person eye examination the same day.
