Vomiting and diarrhea: causes, home care and when to get checked
Most vomiting and diarrhea comes from a stomach virus or food poisoning and clears up in one to three days. The main danger is dehydration. Sip fluids often, watch how much you pee, and get checked if you can't keep liquids down or the diarrhea lasts more than three days.
Norovirus symptoms usually start 12 to 48 hours after exposure, and most people feel better in 1 to 3 days, according to the CDC.
Small, frequent sips of fluid stay down better than big gulps when you have been throwing up.
Antibiotics do not help a stomach virus, because they work on bacteria, not viruses.
See a provider for diarrhea that lasts more than 3 days, a fever over 102°F, bloody stools or signs of dehydration.
Stay home for 48 hours after your symptoms stop so you don't pass a stomach bug to others.
What usually causes vomiting and diarrhea?
When vomiting and diarrhea start suddenly, the cause is usually an infection of the stomach and intestines. People often call this the stomach flu, but it has nothing to do with influenza. It is called gastroenteritis, and viruses cause most cases.
The CDC lists diarrhea, vomiting, nausea and stomach pain as the most common norovirus symptoms. Fever, headache and body aches can come with them. Norovirus spreads through close contact with a sick person, through food or drinks, and from surfaces you touch before touching your mouth.
Stomach viruses, such as norovirus, which spread quickly through homes, schools and daycares
Food poisoning from germs such as Salmonella, Campylobacter or E. coli
Medicines, especially antibiotics, which can upset the gut
Travel, when food or water carries germs your body is not used to
Other triggers, such as too much alcohol, motion sickness or early pregnancy
Stomach bug or food poisoning? How to tell them apart
Timing is the strongest clue. The CDC notes that symptoms start at different times depending on the germ. Think back to what you ate and who around you is sick.
When symptoms usually start, by cause (CDC)
Likely cause
Symptoms usually start
Clues
Norovirus (stomach bug)
12 to 48 hours after exposure
Sudden vomiting and watery diarrhea; others at home or school often sick too
Staph food poisoning
30 minutes to 8 hours after eating
Forceful vomiting soon after a shared meal
Salmonella
6 hours to 6 days
Diarrhea, fever and stomach cramps
Campylobacter
2 to 5 days
Diarrhea that may be bloody, often with fever
E. coli
3 to 4 days
Bad cramps, sometimes bloody diarrhea
Medicine side effect
After starting a new medicine
Loose stools without fever; no one else is sick
You often can't be sure of the cause at home, and that's okay. Care for both starts the same way: replace the fluid your body is losing.
How to care for vomiting and diarrhea at home
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Most adults and children get through a stomach bug at home. Your main job is to keep fluids going in faster than they are going out.
Let your stomach settleAfter you vomit, give your stomach a short rest. Then start with a few small sips rather than a full glass.
Sip oftenTake small sips of water every few minutes, or suck on ice chips. MedlinePlus also suggests drinks with electrolytes for adults. Do not take salt tablets.
Use an oral rehydration solution for kidsThe American Academy of Pediatrics (AAP) recommends store-bought electrolyte solutions. Soda, juice, sports drinks and homemade mixes have the wrong balance of sugar and salt for children.
Eat when you feel hungryOnce vomiting stops, go back to your usual foods slowly. Small, plain meals are easier on your stomach at first.
Check before using medicineThe AAP says over-the-counter anti-diarrhea medicine is not recommended for children under 2 and can be harmful in older children. Ask a doctor first.
Clean up wellWash your hands with soap and water for at least 20 seconds, clean surfaces you touched, and wash soiled laundry in hot water.
How long to wait before getting checked
Most stomach viruses improve in one to three days. For adults, the CDC advises seeing a doctor if diarrhea lasts more than 3 days. For children, the AAP says to call if vomiting lasts more than 12 to 24 hours or fever lasts more than 24 to 48 hours.
When should you go to urgent care for vomiting or diarrhea?
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Watch the trend, not just the symptoms. If you are slowly keeping more fluid down, home care is working. If you are getting weaker or more dried out, it is time to be seen.
Usually fine to manage at home
Vomiting that is easing within a day
Diarrhea without blood, improving after 1 to 3 days
You can keep small sips down
You are still peeing every few hours
Low fever that responds to rest and fluids
Come in to urgent care
Diarrhea lasting more than 3 days
Fever over 102°F
Any blood in the stool
Vomiting so often you can't keep liquids down
Mild dehydration: dry mouth, dark urine, dizziness when you stand
A child vomiting more than 12 to 24 hours
Pregnancy with fever and flu-like symptoms
You can walk in or book a visit online before you leave home. If you have any of the severe warning signs listed at the bottom of this page, go to the nearest emergency room instead.
What happens at our Westmont, IL clinic
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Urgent Care Center of Westmont, also known as Immediate Care Center of Westmont, sees children and adults with stomach illness at two Westmont, IL clinics, open 7 days a week. Our team is led by board-certified physicians.
Questions first. When it started, what you ate, recent travel, medicines, and whether others at home are sick.
A focused exam. Your clinician checks your belly and looks for signs of dehydration, such as a fast heart rate, low blood pressure or a dry mouth.
Lab tests when they help. These may include a stool test, a urine test or blood work, for example when there is blood in the stool or symptoms last longer than expected.
A treatment plan. Care centers on replacing fluids and salts. Your clinician may recommend medicine for nausea or other prescription medicine when appropriate.
Clear next steps. You leave knowing what to drink, what to eat and which signs mean you should come back.
Antibiotics only help certain bacterial infections, so your clinician will explain whether they make sense for you. Learn more on our pages for stomach bug care, food poisoning and diarrhea treatment.
Vomiting and diarrhea in babies, kids and older adults
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Young children and older adults lose fluid faster and show dehydration in different ways, so watch them closely.
Babies and children
Keep breastfeeding. The AAP says breastfeeding should continue through a stomach illness.
If your child is vomiting, offer an electrolyte solution in small amounts, often with a spoon or syringe.
Watch for crying with few or no tears, unusual sleepiness or fussiness, and fewer wet diapers. The CDC lists these as signs of dehydration.
Call the doctor if your child refuses to drink, has a swollen belly, or has green or bloody vomit.
MedlinePlus notes that older adults and people with conditions such as diabetes are at higher risk of dehydration. Water pills and some blood pressure medicines add to that risk. Dizziness when standing can lead to a fall, so get up slowly and have help nearby. Our guide to dizziness covers this in more detail.
How to stop a stomach bug from spreading
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Norovirus spreads easily, and the CDC says people can still spread it for days after they feel better. A few habits protect the rest of your household.
Wash hands with soap and water for at least 20 seconds, especially after using the bathroom and before eating or cooking.
Clean and disinfect counters, faucets, toilets and other surfaces after someone is sick.
Wash soiled clothes and bedding in hot water.
Cook shellfish thoroughly and wash fruits and vegetables.
Stay home from work, school or daycare for 48 hours after symptoms stop.
If fever is part of the picture, our fever guide explains when it is safe to return to school or work. For an overview of every symptom we cover, visit Check Your Symptoms.
Most stomach bugs last one to three days. The CDC says norovirus symptoms usually start 12 to 48 hours after exposure and that most people feel better within 1 to 3 days. You can still spread the virus for a few days after you feel well, so keep washing your hands and stay home for 48 hours after symptoms stop.
Should I go to urgent care for vomiting and diarrhea?
Yes, if diarrhea lasts more than 3 days, you have a fever over 102°F, you see blood in your stool, or you can't keep liquids down. Mild dehydration, such as a dry mouth, dark urine or dizziness when standing, is also a reason to come in. Severe dehydration, fainting or confusion needs the nearest emergency room.
What should I drink after throwing up?
Start with small sips of water, ice chips or an electrolyte drink every few minutes. For children, the AAP recommends a store-bought oral rehydration solution rather than soda, juice or homemade mixes. If the small sips stay down, slowly drink more. Big gulps right after vomiting often come back up.
How do I know if I'm dehydrated?
Early signs of dehydration include thirst, a dry or sticky mouth, peeing less, darker yellow urine, headache and muscle cramps, according to MedlinePlus. In children, look for crying with few or no tears, fewer wet diapers and unusual sleepiness. Very little urine, confusion or a racing heartbeat are signs of severe dehydration that need emergency care.
Is it food poisoning or a stomach bug?
Timing is the strongest clue, but you often can't be sure. Vomiting within a few hours of a meal points to some types of food poisoning. A stomach bug that is going around your home or school usually starts 12 to 48 hours after exposure. Home care is the same for both: replace fluids and rest.
Can I give my child medicine for diarrhea?
Ask a doctor first. The AAP says over-the-counter anti-diarrhea medicine is not recommended for children under 2 and can be harmful in older children. Fluids are the main treatment. An oral rehydration solution replaces the water and salts your child is losing, and most kids can go back to their usual food once vomiting stops.
Do antibiotics help vomiting and diarrhea?
Usually not. Most cases come from viruses, and the CDC notes that antibiotics do not work against viruses. Some bacterial infections or travel-related illnesses may need treatment, which is why a clinician may ask about food, travel and recent medicines. They may also order a stool test before deciding.
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