Most cases of traveler’s diarrhea resolve within a few days with fluids and over-the-counter medications. The key is to start replacing lost water and electrolytes immediately, use symptom-relief medications to get through the worst of it, and save antibiotics for moderate to severe episodes. Here’s how to handle each step.
Start With Fluids, Not Medication
Dehydration is the real danger with traveler’s diarrhea, not the diarrhea itself. Every loose stool pulls water and electrolytes out of your body, and in a hot climate you’re already losing more fluid than usual through sweat. The priority in the first hours is replacing what you’re losing.
Plain water helps, but it doesn’t contain the sodium and sugar your gut needs to absorb fluid efficiently. An oral rehydration solution works far better. You can buy rehydration packets at pharmacies worldwide, or make your own with ingredients available almost anywhere: combine 4 cups of water with half a teaspoon of table salt and 2 tablespoons of sugar. Sip steadily rather than gulping large amounts, which can trigger nausea. If the taste is hard to get down, chicken broth with added sugar or diluted juice with a pinch of salt are reasonable substitutes. The goal is to keep your urine a pale yellow color.
Over-the-Counter Symptom Relief
Two pharmacy staples can reduce your time spent in the bathroom: loperamide (sold as Imodium) and bismuth subsalicylate (Pepto-Bismol).
Loperamide slows the contractions of your intestines, giving your body more time to absorb water from stool. The standard approach for adults is to take two caplets (4 mg total) after the first loose bowel movement, then one caplet (2 mg) after each subsequent loose stool, up to a maximum of 8 caplets (16 mg) in 24 hours. For many people, this alone cuts the number of bathroom trips in half within a few hours.
Bismuth subsalicylate takes a different approach. It reduces inflammation and the amount of fluid your intestines secrete. It’s gentler than loperamide and works well for milder cases, though it can turn your tongue and stool black (harmless, but surprising if you’re not expecting it). Avoid it if you’re allergic to aspirin, since it contains a related compound.
One important rule: do not use loperamide if you have a high fever or bloody stools. Slowing your gut when an invasive infection is present can make things worse. In those situations, you need an antibiotic, not a gut-slowing medication.
When Antibiotics Are Needed
Mild traveler’s diarrhea, a few loose stools a day without fever, typically doesn’t require antibiotics. But moderate to severe episodes, where you’re having frequent watery stools that interfere with your plans, or any episode involving fever or blood, respond faster with antibiotic treatment. Most bacterial causes of traveler’s diarrhea clear in one to three days with the right antibiotic, compared to three to five days without one.
Many travel medicine providers will prescribe antibiotics in advance so you have them on hand. The CDC lists several options, and which one works best depends on where you’re traveling.
Azithromycin
This is the most versatile choice. It works against a broad range of bacteria and is the preferred treatment if you have bloody diarrhea or a high fever. The simplest regimen is a single 1,000 mg dose, though splitting that into two 500 mg doses on the same day reduces the nausea some people experience. A three-day course of 500 mg per day is another option. Azithromycin is the go-to antibiotic for travelers heading to Southeast Asia, where many common diarrhea-causing bacteria have become resistant to other antibiotics.
Fluoroquinolones
Ciprofloxacin and levofloxacin are effective for traveler’s diarrhea in most regions, and ciprofloxacin can work as a single 750 mg dose. However, resistance to these drugs is now widespread in South and Southeast Asia, so they’re not a reliable first choice if you’re traveling there. They also shouldn’t be used when Campylobacter, Salmonella, or Shigella infections are suspected.
Rifaximin
This antibiotic stays almost entirely in your gut rather than being absorbed into your bloodstream, which means fewer side effects. It’s taken as 200 mg three times a day for three days. The catch: it only works against noninvasive strains of E. coli, the most common but not the only cause of traveler’s diarrhea. If you have fever or bloody stools, rifaximin is not the right drug. If symptoms aren’t improving within 24 to 48 hours, you should switch to a different antibiotic.
Combining Loperamide With an Antibiotic
For moderate to severe cases, taking loperamide alongside an antibiotic is a well-supported strategy. The antibiotic kills the bacteria while loperamide controls symptoms in the meantime. This combination tends to shorten the illness more than either treatment alone. Just follow the same loperamide limits: no more than 16 mg in 24 hours, and stop if you develop fever or bloody stools.
What to Eat During Recovery
You don’t need to starve yourself. Eating small, bland meals helps your gut recover. Stick with simple carbohydrates like white rice, plain bread, crackers, and bananas. Avoid dairy, caffeine, alcohol, and greasy or spicy foods until your stools return to normal. These can irritate an already inflamed gut and trigger more cramping.
Probiotics are sometimes recommended for traveler’s diarrhea, but the evidence that they shorten an active episode is mixed. They’re unlikely to cause harm, but they’re also not a substitute for rehydration and appropriate medication.
Signs That Need Medical Attention
Most traveler’s diarrhea is unpleasant but manageable. A few warning signs indicate something more serious is happening:
- Bloody or black stools, which suggest an invasive infection damaging the intestinal lining
- Fever above 102°F (39°C), which points to a more aggressive bacterial or parasitic cause
- Diarrhea lasting more than two days without improvement despite treatment
- Severe abdominal or rectal pain
- Signs of dehydration, including dizziness, dark urine, dry mouth, or confusion
For children, watch for dry mouth, crying without tears, unusual sleepiness, or fewer wet diapers than normal. These signs of dehydration develop faster in young children than in adults.
Preparing Before You Travel
The best time to plan for traveler’s diarrhea is before you leave home. A visit to a travel medicine clinic four to six weeks before departure gives you time to get prescriptions for antibiotics and stock up on loperamide and rehydration packets. Having these in your bag means you can start treatment within hours of the first symptoms rather than searching for a pharmacy in an unfamiliar city.
Pack a small treatment kit: a course of antibiotics (your provider will choose based on your destination), loperamide caplets, oral rehydration salt packets, and bismuth subsalicylate tablets. This kit takes up almost no space in luggage and can save you days of misery. If you’re traveling to Southeast Asia specifically, make sure your antibiotic is azithromycin, since fluoroquinolone resistance is common in that region.