Sudden, watery diarrhea is almost always a short-lived gut infection (a stomach bug) or food poisoning, and most cases settle within 2 to 3 days. The single most important step is to keep sipping fluids — water plus an oral rehydration or electrolyte solution — so you don't get dehydrated. For uncomplicated cases in adults, a licensed clinician can review your symptoms online and prescribe anti-nausea or anti-diarrheal medication the same day when it's safe and appropriate.
Seek emergency care if: you see blood or black, tarry stools, have a fever above 102°F, severe constant belly pain, or signs of dehydration like dizziness, very dark urine, or no urination for 8+ hours.
See a clinician nowWhat diarrhea actually is
Diarrhea means passing loose or watery stools more often than normal — generally three or more times in a day. Acute diarrhea comes on suddenly and lasts a few days; most of it is caused by a viral infection (like norovirus or rotavirus), bacteria from contaminated food or water, or a reaction to medication. It is your gut's way of flushing out an irritant, which is why it usually doesn't need to be stopped completely.
Because you lose water and salts with every loose stool, the real risk of ordinary diarrhea is dehydration — not the diarrhea itself. That's why fluid replacement is the foundation of treatment.
What it looks like — common signs
If these describe what you're experiencing and you have no red flags, telehealth is a reasonable next step:
What to do right now
The goal in the first 24 hours is to stay ahead of dehydration and let your gut settle:
- Sip fluids steadily — water, broth, or an oral rehydration solution (ORS). Small frequent sips beat large gulps if you're nauseated.
- Eat bland foods when you can tolerate them — bananas, rice, toast, crackers, applesauce.
- Avoid alcohol, caffeine, very fatty foods, and large amounts of dairy until you recover.
- Use loperamide (Imodium) cautiously — it can ease ordinary watery diarrhea, but skip it if you have a high fever or bloody stools.
- Wash your hands well — many causes are contagious, so good hygiene protects others.
The diarrhea isn't the danger — dehydration is. Keep fluids going in, and most cases resolve on their own.
How a clinician can help online
For uncomplicated acute diarrhea in adults, telehealth works well. A clinician reviews your symptoms, timeline, travel and food history, and any red flags, then can recommend a rehydration plan and prescribe an anti-nausea medication (such as ondansetron) or an anti-diarrheal when appropriate. If your history suggests a specific bacterial or parasitic cause — or if testing is needed — they'll direct you to the right next step.
Telehealth is NOT the right path for: diarrhea with blood or black stools, high fever, severe or worsening abdominal pain, signs of significant dehydration, symptoms lasting more than a week, recent hospitalization or antibiotics (possible C. diff), or anyone who is very young, elderly, pregnant, or immunocompromised — these need in-person evaluation.
How diarrhea is treated
The backbone of treatment is fluid and electrolyte replacement. For symptom relief, clinicians may use loperamide for non-bloody, non-febrile diarrhea, or bismuth subsalicylate (Pepto-Bismol). Ondansetron can control associated nausea so you can keep fluids down. Antibiotics are reserved for confirmed or strongly suspected bacterial or parasitic infections — they're not used for routine viral diarrhea, where they don't help and can prolong symptoms.
How long does it last?
Most acute diarrhea improves within 2 to 3 days and fully resolves within a week. Viral causes tend to be shorter; food poisoning often peaks fast and then clears. If loose stools persist beyond 14 days, it's considered persistent or chronic diarrhea and warrants an in-person workup to look for causes like IBS, inflammatory bowel disease, or a lingering infection.
Frequently asked questions
When should I worry about diarrhea?
Seek care for diarrhea lasting more than 2–3 days, blood or black tarry stools, a fever above 102°F, signs of dehydration, or severe constant abdominal pain. Otherwise most acute diarrhea improves on its own with hydration.
Should I take loperamide (Imodium)?
OTC loperamide can reduce frequency for ordinary watery diarrhea, but avoid it if you have a high fever or bloody stools, because slowing the gut can worsen certain bacterial infections. A clinician can confirm it's safe for you.
Can I get treated for diarrhea online?
Yes. For uncomplicated acute diarrhea in adults, a clinician can review your symptoms online, guide rehydration, and prescribe anti-nausea or anti-diarrheal medication when appropriate. Cases with red flags are sent to in-person care.
What should I eat with diarrhea?
Stick to bland, easy-to-digest foods like bananas, rice, toast, crackers, and broth, and keep sipping water or an oral rehydration solution. Avoid alcohol, caffeine, very fatty foods, and large amounts of dairy until you recover.
Do I need antibiotics?
Most acute diarrhea is viral and does not need antibiotics. They're reserved for specific bacterial or parasitic infections, often confirmed by stool testing. Unnecessary antibiotics can prolong symptoms and drive resistance.
