Food Poisoning and Traveler's Diarrhea in Sri Lanka

Traveler’s diarrhea hits roughly half of all visitors to South Asia at some point during a longer stay. It’s almost never dangerous in healthy adults, but it can ruin a few days of your trip and, if it becomes severe, lead to dehydration that does need treatment. Sri Lankan food is one of the great pleasures of being here — the goal isn’t to avoid it, but to know how to manage things when they go sideways.

What causes it

Most cases are bacterial — usually a strain of E. coli, sometimes Campylobacter, Salmonella, or Shigella. Less commonly, viruses (norovirus) or parasites (Giardia, Cryptosporidium) are responsible. The route is almost always contaminated water or food — raw vegetables washed in tap water, ice, unpasteurised dairy, undercooked meat, food left at room temperature, or anything handled by someone who hasn’t washed their hands.

Symptoms

Bacterial traveler’s diarrhea usually starts twelve to seventy-two hours after exposure. Watery diarrhea, cramping, sometimes vomiting, occasionally fever. It usually peaks at twenty-four to forty-eight hours and resolves in three to five days without specific treatment.

Viral cases are similar but often include more vomiting and lower fevers. Parasitic cases come on more slowly, usually after a week, and last longer.

Treatment — what to do at home

Most cases are manageable without antibiotics. The priorities are:

1. Replace fluids and electrolytes constantly. Oral rehydration salts (ORS) are the single most important treatment. You can buy them at any pharmacy, including ours. Mix one sachet with the volume of water on the packet, and sip throughout the day. Plain water is not enough on its own — you lose salts, not just water.
2. Eat lightly when you can. Plain rice, bananas, toast, plain crackers, boiled potato. Avoid dairy, fatty foods, and spice while you’re acutely ill. The old “starve the diarrhea” advice is wrong — your gut heals faster with some food in it.
3. Anti-motility medication (loperamide, Imodium) is fine for adults with watery diarrhea and no blood, no high fever, and no severe abdominal pain. It buys you a few hours’ relief — useful for long bus rides — but doesn’t cure the underlying infection.
4. Bismuth subsalicylate (Pepto-Bismol) can help with cramping and mild diarrhea.

When to see a doctor

Come and see us if any of these apply:

• Blood or mucus in the stool
• High fever (over 39°C)
• Severe abdominal pain
• Vomiting that won’t stop, leaving you unable to keep fluids down
• Signs of dehydration: dizziness on standing, dark or scanty urine, dry mouth, racing heart, confusion
• Symptoms lasting more than five days
• You’re elderly, very young, pregnant, or have underlying health conditions

We can run a quick stool test if needed, prescribe antibiotics for bacterial cases that aren’t resolving (we usually use azithromycin in Sri Lanka, as resistance to older drugs has grown), and give an IV drip if dehydration is significant. Most people who come to us severely dehydrated walk out two hours later feeling close to normal.

Prevention

Sri Lanka has fantastic food, and avoiding everything risky is both unrealistic and a shame. Sensible compromises:

• Drink bottled or filtered water. Check that the seal on the bottle is intact when you buy it.
• Avoid ice in drinks unless you know it’s made from purified water (most restaurants in Arugam Bay do use safe ice, but ask if you’re unsure).
• Hot food, fresh from the kitchen, is generally safe. Cooked-then-cooled buffet food is the riskier category.
• Peel your own fruit or eat fruit you’ve washed in bottled water. Pre-cut fruit at street stalls is higher risk.
• Be cautious with raw salads unless you’re at a place that washes vegetables in purified water (most surf-town tourist restaurants do).
• Be cautious with shellfish, especially in restaurants that don’t look busy.
• Wash hands before eating, or use sanitiser.
• Hot tea and coffee are nearly always safe because of the heat.

If you get sick despite all this, you’re not alone — it happens to almost everyone given enough time in the country. The body’s gut bacteria gradually adjust, and your tolerance increases over a few weeks.

This article is general health information and not a substitute for medical advice. Severe or prolonged diarrhea needs a doctor.