Most sudden vomiting is caused by a viral stomach bug (gastroenteritis) or food poisoning, and it usually settles on its own within 24 to 48 hours. The most useful step is to rest your stomach, then take tiny, frequent sips of water or an electrolyte solution so you don't get dehydrated. For uncomplicated cases in adults, a licensed clinician can review your symptoms online and prescribe an anti-nausea medication like ondansetron the same day so you can hold fluids down.
Seek emergency care if: you vomit blood or material that looks like coffee grounds, vomit is green or forceful/projectile, you have severe abdominal pain, a stiff neck or severe headache, confusion, or you vomited after a head injury.
See a clinician nowWhat's going on
Vomiting is a forceful reflex that empties the stomach. It's a symptom, not a disease — and most of the time the cause is a temporary irritant: a viral stomach bug, food poisoning, too much alcohol, or motion. Less often it points to something that needs prompt attention, which is why the pattern and accompanying symptoms matter.
As with diarrhea, the main short-term risk of ordinary vomiting is dehydration, because you lose fluid and salts faster than you can replace them. Calming the nausea so you can rehydrate is usually the fastest route to feeling better.
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
- Rest your stomach for 30–60 minutes after vomiting before trying anything.
- Start with tiny sips — a teaspoon of water, an oral rehydration solution, or ice chips every 5–10 minutes, then slowly increase.
- Add bland foods only once fluids stay down — crackers, toast, rice, bananas, broth.
- Avoid alcohol, caffeine, very fatty foods, and large meals until you fully recover.
- Don't lie completely flat right after vomiting; prop yourself up to reduce nausea.
Stop the nausea, sip steadily, and most stomach bugs run their course in a day or two — dehydration is the thing to stay ahead of.
How a clinician can help online
For uncomplicated acute vomiting in adults, telehealth is a good fit. A clinician reviews your symptoms, timeline, food and travel history, medications, and red flags, then can prescribe an antiemetic (most commonly ondansetron) so the nausea calms enough for you to rehydrate. They'll also give a clear plan for when to escalate.
Telehealth is NOT the right path for: vomiting blood or coffee-ground material, green or projectile vomiting, severe abdominal pain, vomiting after a head injury, severe headache or stiff neck, confusion, inability to keep any fluids down for 24+ hours, suspected pregnancy with severe vomiting, or vomiting in infants, older adults, or immunocompromised people — these need in-person care.
How vomiting is treated
Treatment targets the nausea and prevents dehydration. Ondansetron (Zofran) is the most commonly prescribed antiemetic for acute vomiting; other options include promethazine or metoclopramide in select cases. Alongside medication, oral rehydration with an electrolyte solution restores the fluid and salts you've lost. Antibiotics are almost never needed, since most acute vomiting is viral or from a self-limited cause.
How long does it last?
Vomiting from a stomach bug or food poisoning usually peaks within the first several hours and eases within 24 to 48 hours, often followed by a day of diarrhea or fatigue. If you can't keep any fluids down for more than a day, or vomiting drags on beyond 48 hours, get evaluated — persistent vomiting can point to a cause that needs in-person workup.
Frequently asked questions
How do I keep fluids down when I keep throwing up?
Wait 30–60 minutes after vomiting, then take tiny sips of water or an oral rehydration solution every 5–10 minutes, starting with a teaspoon and gradually increasing. Ice chips and clear broth also help. Large amounts at once often trigger more vomiting.
Can a doctor prescribe anti-nausea medication online?
Yes. For uncomplicated acute vomiting in adults, a clinician can review your symptoms by telehealth and prescribe an antiemetic such as ondansetron when appropriate, so you can keep fluids down while the cause resolves.
When is vomiting an emergency?
Seek emergency care for vomiting blood or coffee-ground material, green or projectile vomiting, severe abdominal pain, a stiff neck or severe headache, confusion, signs of dehydration, or vomiting after a head injury.
How long does vomiting usually last?
Vomiting from a stomach bug or food poisoning usually peaks in the first several hours and settles within 24–48 hours. If you can't keep any fluids down for over 24 hours, or it persists past a couple of days, get evaluated.
What should I eat after vomiting stops?
Once you can hold down fluids, start with bland foods like crackers, toast, rice, bananas, or broth. Reintroduce normal food slowly over a day, and avoid alcohol, caffeine, very fatty foods, and large meals until you feel normal.
