Medically reviewed by Dr. Ponlawat Pitsuwan, Physician, Takecare Clinic Phuket. Last reviewed: September 2026.
Traveller’s diarrhoea affects a large share of first-time visitors to Southeast Asia, and I see it every day in Phuket. Most cases are mild, but some bacteria common in this region are resistant to older antibiotics. So I choose treatment carefully rather than reaching for the first tablet available.
Traveller’s diarrhoea tends to appear in the first few days of a Phuket holiday, once the new food, heat and ice-filled drinks have had time to work. Unlike a single bad meal, it builds: a few loose stools, some cramping, then the nagging need to stay near a toilet. It is hardest on people moving between beaches, boats and islands, where facilities are not always close. For a healthy adult it is rarely dangerous, but the right antibiotic here differs from what many travellers bring from home.
What counts as traveller’s diarrhoea
Doctors define it as three or more loose stools in 24 hours during or shortly after travel, with at least one other symptom such as cramps, nausea, urgency or fever. Bacteria cause most cases, led by enterotoxigenic E. coli (ETEC), a strain whose toxin makes the gut pour out water, together with Campylobacter, Salmonella and Shigella. In Thailand, Campylobacter is a particularly important cause. The germs travel on food, water, ice and hands carrying traces of faeces, so hand hygiene matters as much as menu choices.
How it differs from food poisoning
Food poisoning follows one specific meal, starts within hours and is usually led by vomiting, a pattern we cover on our food poisoning treatment page. Traveller’s diarrhoea builds over hours to days, is led by diarrhoea, and often no single dish is to blame.
Severity decides the treatment
International travel medicine guidance grades traveller’s diarrhoea by how much it disrupts your day rather than by stool count alone, and that grade guides what we prescribe.
| Grade | What it feels like | What usually helps |
|---|---|---|
| Mild | Annoying but you can carry on with your plans | Oral rehydration, plain food, loperamide if needed |
| Moderate | Distressing, forces you to change plans | Loperamide, with azithromycin considered |
| Severe | Incapacitating, confined to your room | Azithromycin, fluids, doctor review |
| Dysentery | Blood or mucus in the stool, often with fever | Azithromycin, stool test, no loperamide alone |
Azithromycin, not ciprofloxacin: the Southeast Asia rule
Many travellers pack ciprofloxacin, a fluoroquinolone antibiotic, because it has long been a standard choice elsewhere. In Thailand and much of Southeast Asia, Campylobacter has developed high resistance to fluoroquinolones, so they often fail here, and they also carry warnings about tendon and nerve side effects. Azithromycin, a macrolide antibiotic, is the preferred option. Adults usually take a single 1 g dose or 500 mg once daily for 3 days, children receive a weight-based dose, and it can be used in pregnancy. Treatment typically shortens the illness to around a day, and the main side effect is nausea.
What happens when you see us
We ask when it started, how many stools you are passing, whether there is blood or fever and what you have already taken, then check your temperature, pulse, hydration and abdomen. Most people need no tests. A stool test, either a culture or a PCR panel that detects the organism’s genetic material, helps with blood, high fever or symptoms beyond a week, and blood tests for electrolytes and kidney function come back the same day from our on-site laboratory.
Treatment follows the grade: rehydration for everyone, an anti-sickness medicine such as ondansetron if you are vomiting, and azithromycin when the illness is moderate to severe. If you cannot drink enough to keep up, intravenous fluids restore you much faster, as described on our page about IV drip therapy in Phuket.
Self-care that genuinely helps
Oral rehydration salts (ORS) are the backbone: drink a glass after every loose stool, on top of your usual fluids. Keep eating small, simple meals such as rice, noodle soup or bananas, and hold off on alcohol until stools firm up.
Loperamide slows the gut and suits mild to moderate watery diarrhoea in adults: usually 4 mg, then 2 mg after each loose stool, never above the packet maximum, and never alone with blood or fever. Two points are often missed. Severe diarrhoea can stop the contraceptive pill being absorbed, so follow your pill’s missed-dose rules, and medicines such as metformin, diuretics and some blood pressure tablets may need pausing while you are dehydrated.
Island days, boat trips and onward travel
A day trip to Phi Phi or the Similan Islands can mean hours with no toilet. If your symptoms are mild and you have no fever or blood, loperamide on the morning of the trip is reasonable. If you are heading on through Southeast Asia after Phuket, especially somewhere remote, ask about carrying a standby course of azithromycin with clear instructions on when to start it; our travel medicine in Phuket service covers this. For long-haul flights home, keep ORS in your hand luggage.
When to see a doctor
See a doctor if symptoms last more than 3 days despite self-care, you pass more than six loose stools in 24 hours, your temperature reaches 38.5°C, or you cannot keep up with fluids. Pregnant women, older travellers and anyone with inflammatory bowel disease, diabetes, kidney disease or a weakened immune system should come in earlier. Diarrhoea lasting beyond two weeks is no longer typical traveller’s diarrhoea and needs tests for parasites such as Giardia; our broader guide to diarrhoea treatment explains that work-up.
Prevention and early detection
No approach removes the risk entirely, but a few habits lower it. Choose food cooked hot in front of you, fruit you peel yourself and sealed bottled water, and be warier of salads, raw herbs and ice of unknown origin. Preventive antibiotics are not recommended for most travellers because side effects and resistance outweigh the benefit. Early detection means starting ORS at the first loose stool and keeping a rough count of stools, blood and temperature so we can grade your illness quickly.
Where to get treated in Phuket
We treat traveller’s diarrhoea around the clock at three clinics: the Bangtao (Cherngtalay) clinic, our Kata-Karon clinic and the Patong clinic. Walk in without booking, or message us on WhatsApp first so we are ready; you can also phone +66 81 718 9080. You are usually seen within minutes, and our walk-in doctor in Phuket page explains what to expect.
If you would rather not travel, a doctor hotel visit in Phuket brings the consultation, medicines and a drip if needed to your room, 24/7. We direct-bill most travel insurers and supply receipts, a medical report and an itemised invoice for your claim. We confirm the price on WhatsApp before your visit.
Related services and treatments
If your main symptom is a burning pain high in the stomach rather than loose stools, our gastritis treatment page is the better fit. You can browse every other condition on our conditions we treat page.
Summary
Traveller’s diarrhoea is a mostly bacterial illness picked up from food, water and hands, and it usually settles in 3 to 5 days. Rehydration comes first. When an antibiotic is needed in Thailand, azithromycin beats ciprofloxacin because of regional resistance. Start ORS early and see a doctor promptly for blood, fever, dehydration or illness that is not improving.
“Rehydration comes first, antibiotics second. Keep drinking oral rehydration solution and see a doctor if you have blood in your stool or a high fever.”
Dr. Ponlawat Pitsuwan, Physician, Takecare Clinic Phuket
Frequently asked questions
Will travel insurance cover my traveller’s diarrhoea treatment, and what should I expect to pay?
Most travel insurance policies cover sudden illness abroad, including traveller’s diarrhoea, though excesses and conditions vary, so check your policy. We direct-bill most travel insurers and otherwise provide a receipt, medical report and itemised invoice for your claim. The cost depends on whether you need medicines, stool tests or a drip, and we confirm the price on WhatsApp before your visit.
How quickly does azithromycin stop traveller’s diarrhoea?
Most people notice fewer stools and less cramping within 24 hours of the first dose, and many are back to normal by the second day. Keep drinking oral rehydration salts in the meantime, because the fluid you have already lost still needs replacing. If you are no better after 48 hours on treatment, come back so we can reassess and consider a stool test.
Do I need to book, or can I walk in between toilet trips?
You can walk in at any hour without an appointment, and we understand if you need the bathroom as soon as you arrive. All three clinics are open 24/7 and most visits take under 30 minutes. A WhatsApp message on the way helps us get you into a room quickly.
Can a doctor come to my hotel if I cannot leave the bathroom?
Yes. Our doctors come to hotels, villas and condos anywhere in Phuket at any time of day or night. The visiting doctor assesses your hydration, prescribes the right medicines from our pharmacy and can set up an intravenous drip in your room if you are dehydrated. This is often the most comfortable option on a bad first day.
I brought ciprofloxacin from home. Should I take it in Thailand?
We would advise against relying on it. Ciprofloxacin and other fluoroquinolones often fail in Thailand because Campylobacter, a common cause here, is frequently resistant. Azithromycin is the recommended alternative in Southeast Asia. If you have already started ciprofloxacin and are not improving within a day, see us so we can switch your treatment.
Is it safe to take a boat trip or fly while I still have diarrhoea?
With mild watery diarrhoea and no fever or blood, many people manage a boat trip or flight after a dose of loperamide and with ORS to hand. Postpone if you have a fever, blood in your stool, severe cramps or dizziness, because being hours from a toilet or a doctor while dehydrated is genuinely risky. If in doubt, let us assess you first.
Sources
The CDC Yellow Book chapter on travelers’ diarrhea sets out severity grading and antibiotic choice by region. The UK’s TravelHealthPro traveller’s diarrhoea factsheet covers prevention and standby treatment. The NHS page on diarrhoea and vomiting explains rehydration and when to get help.
traveller’s diarrhoea, travelers’ diarrhea, enterotoxigenic Escherichia coli, ETEC, Campylobacter, Shigella, Salmonella, norovirus, Giardia, dysentery, azithromycin, ciprofloxacin, fluoroquinolones, rifaximin, loperamide, ondansetron, oral rehydration salts, stool PCR, CDC Yellow Book, TravelHealthPro, NHS, Phi Phi, Similan Islands, Bangtao, Kata, Karon, Patong, Takecare Clinic Phuket, Dr. Ponlawat Pitsuwan
This page is general health information and not a substitute for a medical consultation.