Pink eye, or conjunctivitis, spreads easily in Thailand during the rainy season, according to the Department of Disease Control (DDC). Most of it is caused by viruses, which antibiotic eye drops do not cure, and it usually clears within one to two weeks. A painful eye, blurred vision or strong sensitivity to light is different: that needs a doctor the same day.
In Thai, epidemic red eye is called rok ta daeng, "red eye disease", and the DDC describes it as a common rainy-season illness that breaks out in schools, nurseries, workplaces and swimming pools. For a traveler it mostly means being careful with hands, towels and water, and knowing which symptoms are more than ordinary pink eye.
This page is general information from the DDC, the US Centers for Disease Control and Prevention (CDC) and the UK's National Health Service (NHS), checked in October 2026. It cannot tell you what is wrong with your eye. Only a doctor who examines it can do that.
Pink eye in Thailand at a glance (checked October 2026)
- Most common cause
- Viruses, most often adenovirus (DDC)
- When
- Common in the rainy season; outbreaks in schools, workplaces and swimming pools (DDC)
- How it spreads
- Tears passed on by hands or shared items, or dirty water in the eye; not by looking at someone or through the air (DDC)
- Usual course
- Starts 1–2 days after contact, worst on days 4–7, clears in about 7–14 days (DDC)
- Antibiotic drops
- Do not help viral pink eye (CDC)
- DDC hotline
- 1422 (in Thai)
Rainy-season outbreaks and dirty water
The DDC lists the usual viruses behind epidemic red eye as adenovirus first, then herpes viruses, enteroviruses and coxsackieviruses. Its disease page says outbreaks are common in the rainy season (roughly May to October in most of Thailand). Our guide to the rainy season describes what those months are like to travel in.
Dirty water is one of the routes the DDC names. Splashes from a flooded street, a muddy waterfall pool or a crowded swimming pool can carry the virus into the eye. The DDC advises rinsing dirt or dirty water out of the eye straight away with clean water. Floodwater carries other risks too, including leptospirosis; our page on leptospirosis and melioidosis explains them.
We did not find a current DDC case count or outbreak alert for 2025 or 2026, so we cannot tell you how many cases there are this year. If you are traveling with children, ask your hotel or school whether there is an outbreak locally.
How it spreads, and how not to catch it
Red eye spreads through tears and eye discharge. The DDC says it passes from hands, towels, pillowcases and other shared items to the next person's eye. It is not caught by looking at someone, through the air or by sharing food. The CDC says viral and bacterial pink eye are both very contagious.
- Wash your hands often, and always before touching your eyes or putting in contact lenses.
- Use your own towel and pillowcase; do not share eye make-up or eye drops.
- Avoid swimming pools during a local outbreak, as the DDC advises.
- If one person in your group has red eye, give them their own towel and wash it separately.
If you have it, the DDC asks patients to stay away from school or work for at least three days. For a traveler, that means skipping the hostel pool, the dive boat and the cooking class for a few days rather than passing it on.
Contact lenses, swimming and the sea
Contact lenses change the risks. The CDC's advice is to keep lenses away from all water, which means taking them out before swimming or showering, never storing them in water and avoiding sleeping in them. Poor lens care raises the risk of keratitis, an infection of the clear front surface of the eye, and the CDC says some types, such as Acanthamoeba and fungal keratitis, can lead to vision loss.
Both the DDC and the CDC say to stop wearing lenses while you have pink eye, until the eye has cleared. Bring a pair of glasses for that reason alone. The NHS adds that a lens wearer who has conjunctivitis together with spots on the eyelid should see a doctor.
Buying lenses, solution and glasses in Thailand is a separate subject: our guide to buying glasses and contact lenses in Thailand covers optical shops and the risks of cosmetic lenses.
A red, painful eye in a contact lens wearer is not ordinary pink eye until a doctor says so. Take the lenses out, keep them and the case to show the doctor, and go to a hospital eye clinic the same day rather than treating it with drops from a pharmacy.
Eye drops from a pharmacy or a doctor?
Thai pharmacies sell eye drops over the counter, such as lubricating drops for dry eyes; our older article on what you can buy at Thai pharmacies describes how they work. A pharmacist can help with dryness or irritation from dust and air-conditioning.
Antibiotic drops are a different matter. The CDC says plainly that antibiotics will not improve viral pink eye, which is the common outbreak type, and the NHS says antibiotics are used only for bacterial conjunctivitis. We could not confirm how the Thai FDA classifies antibiotic eye drops, so we cannot say whether a pharmacy may sell them without a prescription. Our advice is simple: see a doctor before using antibiotic drops, so that someone decides whether they are needed at all.
Mild bacterial pink eye usually clears in two to five days, according to the CDC, and viral pink eye in one to two weeks, sometimes two to three. If the eye is not getting better within about a week, the NHS says to see a doctor.
Red flags: when to see a doctor quickly
The CDC and the NHS list symptoms that need medical attention rather than waiting. See a doctor promptly, and urgently if several apply, if you have:
- pain in the eye, not just grittiness;
- sensitivity to light;
- blurred vision that does not clear when you wipe away the discharge, or changes in vision such as wavy lines or flashing lights;
- a very red eye, or symptoms that are getting worse;
- bacterial pink eye that has not improved after 24 hours of antibiotics prescribed by a doctor;
- a weakened immune system;
- a baby under 30 days old with red, sticky eyes, which the NHS says needs urgent help.
The NHS also notes that some sexually transmitted infections can cause conjunctivitis, so mention any recent risk to the doctor. If dirt or dirty water gets in the eye, the DDC advises rinsing it out with clean water; if something stays stuck, get help rather than rubbing. For an emergency, call 1669; our emergency numbers guide explains what to say.
Finding an eye doctor in Thailand
In Thailand, an eye doctor (ophthalmologist) is usually found in a hospital eye department rather than in an optical shop. Larger private hospitals list their eye centers on their websites; call ahead to ask whether you can be seen the same day. Government hospitals are cheaper but busier, with less English spoken. Our guide to hospitals in Thailand explains the difference and how payment and insurance guarantees work.
The UK government notes that there is no reciprocal healthcare between the UK and Thailand, so you or your insurer pay for the visit. Keep the receipt and the doctor's note for a claim; our page on travel insurance for Thailand covers what a policy should include. In the smoky season in the north, irritated eyes are more often caused by the air than by an infection; our page on air pollution covers that.
Frequently asked questions
Is pink eye common in Thailand?
The Department of Disease Control says epidemic red eye is common in the rainy season, with outbreaks in schools, nurseries, workplaces and swimming pools. We found no current national case count, so we cannot say how many cases there are in 2026.
Can I buy antibiotic eye drops at a Thai pharmacy?
Pharmacies sell many eye drops, but we could not confirm the Thai FDA rules for antibiotic drops. More importantly, the CDC says antibiotics do not help viral pink eye, the usual outbreak type. See a doctor before using them.
Can I swim with pink eye?
Better not. The DDC names swimming pools as places where outbreaks happen and advises avoiding swimming during an outbreak. People with red eye should also stay home for at least three days, and should not wear contact lenses until the eye has cleared.
How long does pink eye last?
Viral pink eye usually clears in about 7 to 14 days, according to the DDC and the CDC, and mild bacterial pink eye in two to five days. If your eye is not better after about a week, or if it hurts, see a doctor.
Sources
- Department of Disease Control (Thailand) – Red eye disease (in Thai) (checked October 2026)
- US Centers for Disease Control and Prevention – About pink eye (15 April 2024) (checked October 2026)
- US Centers for Disease Control and Prevention – Treatment of pink eye (checked October 2026)
- NHS – Conjunctivitis (last reviewed 23 April 2024) (checked October 2026)
- US Centers for Disease Control and Prevention – Preventing contact lens infections (27 May 2025) (checked October 2026)
- UK Government – Healthcare and medical services in Thailand (checked October 2026)