For most cases of diarrhea, the two most effective over-the-counter options are loperamide (Imodium) and bismuth subsalicylate (Pepto-Bismol). Loperamide slows down intestinal movement to reduce the frequency of loose stools, while bismuth subsalicylate soothes the stomach lining and can also help with nausea and cramping. Which one you reach for depends on your symptoms, your age, and how long the diarrhea has lasted.
Most acute diarrhea resolves on its own within a few days. But choosing the right combination of fluids, food, and medication can make a real difference in how quickly you recover and how miserable those days feel.
Loperamide: The Fastest OTC Option
Loperamide works by slowing the muscles in your intestines, giving your body more time to absorb water from stool. This makes bowel movements less frequent and more solid. It’s the go-to choice when your main problem is frequent, watery trips to the bathroom.
The standard approach for adults is to take two capsules (4 mg total) after the first loose stool, then one capsule (2 mg) after each additional loose stool. The maximum is 8 capsules (16 mg) in 24 hours for the capsule form, or 4 tablets (8 mg) for the over-the-counter tablet form. Children under 13 should not take loperamide without a doctor’s guidance.
One important caveat: loperamide treats the symptom, not the cause. If your diarrhea is from a bacterial infection, slowing your gut down can actually keep the bacteria trapped inside longer. Skip loperamide if you have a fever, bloody stools, or suspect food poisoning, and talk to a doctor instead.
Bismuth Subsalicylate for Milder Symptoms
Bismuth subsalicylate is a better fit when diarrhea comes with an upset stomach, heartburn, or nausea. It coats the stomach lining and has mild anti-inflammatory and antimicrobial effects. It’s also commonly recommended for preventing traveler’s diarrhea.
Because this medication contains a compound related to aspirin, it’s not safe for everyone. You should avoid it if you have an aspirin allergy, a bleeding disorder, gout, kidney disease, or a stomach ulcer. It’s also not recommended for children under 12 or for anyone who is breastfeeding, as studies have shown harmful effects on infants. If you’re already taking aspirin or any other salicylate-containing medication, combining them raises the risk of overdose.
Don’t be alarmed if your tongue or stool turns black while taking it. That’s a harmless and temporary side effect of the bismuth.
Fluids Matter More Than Food
Dehydration is the biggest risk with diarrhea, especially in young children and older adults. Water alone isn’t ideal because it doesn’t replace the electrolytes (sodium, potassium) you’re losing. Oral rehydration solutions, diluted broths, and sports drinks are better choices. Sip steadily rather than gulping large amounts at once.
For food, most experts no longer recommend the traditional BRAT diet (bananas, rice, applesauce, toast) as a strict protocol. The National Institute of Diabetes and Digestive and Kidney Diseases notes that in most cases, you can return to your normal diet when you feel ready to eat. The main things to avoid while recovering are dairy (if it seems to worsen symptoms), very fatty or greasy foods, alcohol, and caffeine, all of which can irritate an already sensitive gut.
Probiotics: A Helpful Add-On
The probiotic yeast Saccharomyces boulardii has the strongest evidence behind it for acute diarrhea. A meta-analysis published by the American Academy of Pediatrics found that it reduced the duration of diarrhea by roughly 20 hours compared to placebo and significantly lowered stool frequency by the second and third day. It was also found to be safe with no notable side effects.
Other probiotic strains, particularly Lactobacillus-based products, are widely available and may help, though the evidence is less consistent. If you want to try a probiotic, look for products that specifically list the strain (not just “live cultures”) and take them alongside your other treatments, not as a replacement.
Teas and Home Remedies
Green tea and black tea both have some supporting evidence for diarrhea relief. A 2022 study found that green tea extract significantly improved diarrhea symptoms and shortened recovery time in children with stomach flu. Black tea has also shown modest benefits for stool frequency and consistency in a smaller study. Peppermint and ginger teas are more commonly used for nausea and cramping than for diarrhea itself, but they can ease the general discomfort that comes along with it.
These are gentle, low-risk options that work best as complements to proper hydration and, if needed, medication.
What to Use for Children
Children need a different approach than adults. Loperamide is only approved for children 13 and older (in the OTC form), and bismuth subsalicylate should not be used in children under 12. The priority for kids is preventing dehydration with an oral rehydration solution.
The World Health Organization recommends zinc supplementation for children with acute diarrhea: 20 mg per day for 10 to 14 days, or 10 mg per day for infants under six months. Zinc has been shown to reduce the duration and severity of diarrheal episodes in children and is widely used in pediatric care worldwide. It’s available as a supplement in most pharmacies.
Watch children closely for signs of dehydration: no wet diaper for three or more hours, a dry mouth or tongue, crying without tears, unusual sleepiness, or a sunken appearance around the eyes, cheeks, or belly. In children, see a doctor if diarrhea doesn’t improve within 24 hours, or immediately if there’s a fever above 102°F or blood in the stool.
When Diarrhea Needs More Than Home Treatment
Acute diarrhea lasts less than two weeks. If it stretches past two weeks, it’s considered persistent. Past four weeks, it’s chronic, and almost always needs medical evaluation to identify an underlying cause like irritable bowel syndrome, inflammatory bowel disease, or a food intolerance.
For adults, seek medical care if diarrhea lasts more than two days without any improvement, if you see blood or black color in your stool, if you have severe abdominal or rectal pain, or if you notice signs of dehydration: excessive thirst, very dark urine, dizziness, or little to no urination.
Traveler’s Diarrhea and Antibiotics
Antibiotics aren’t useful for most diarrhea, which is typically caused by viruses. The major exception is traveler’s diarrhea, where bacteria are the most common culprit. The CDC classifies traveler’s diarrhea by how much it disrupts your day. Mild cases (annoying but manageable) don’t need antibiotics. Moderate cases (interfering with your plans) can benefit from them. Severe cases (incapacitating, or involving bloody stools) should be treated with antibiotics.
If you’re planning a trip to a high-risk destination, ask your doctor about carrying a course of antibiotics as a precaution. In Southeast Asia and other regions with high rates of antibiotic-resistant bacteria, certain antibiotics work better than others, so the prescription should be tailored to your destination. Antibiotics can also be combined with loperamide for faster relief in moderate to severe cases.