Learn more about vomiting or diarrhoea: introduction
Gastroenteritis is a very common condition that causes diarrhoea and vomiting. It's usually caused by a bacterial or viral tummy bug.
It affects people of all ages, but is particularly common in young children.
Gastroenteritis can be very unpleasant, but it usually clears up by itself within a week. You can normally look after yourself or your child at home until you're feeling better.
Try to avoid going to your GP, as gastroenteritis can spread to others very easily. Call NHS 111 or your GP if you're concerned or need any advice.
This page covers:
Symptoms of gastroenteritis
The main symptoms of gastroenteritis are:
- sudden, watery diarrhoea
- feeling sick
- vomiting, which can be projectile
- a mild fever
The symptoms usually appear up to a day after becoming infected. They typically last less than a week, but can sometimes last longer.
What to do if you have gastroenteritis
If you experience sudden diarrhoea and vomiting, the best thing to do is stay at home until you're feeling better. There's not always a specific treatment, so you have to let the illness run its course.
You don't usually need to get medical advice, unless your symptoms don't improve or there's a risk of a more serious problem (see When to get medical advice).
To help ease your symptoms:
- Drink plenty of fluids to avoid dehydration – You need to drink more than usual to replace the fluids lost from vomiting and diarrhoea. Water is best, but you could also try fruit juice and soup.
- Take paracetamol for any fever or aches and pains.
- Get plenty of rest.
- If you feel like eating, try small amounts of plain foods, such as soup, rice, pasta and bread.
- Use special rehydration drinks made from sachets bought from pharmacies if you have signs of dehydration, such as a dry mouth or dark urine – read about treating dehydration.
- Take anti-vomiting medication (such as metoclopramide) and/or antidiarrhoeal medication (such as loperamide) if you need to – some types are available from pharmacies, but check the leaflet that comes with the medicine. You can also ask your pharmacist or GP for advice about whether they're suitable.
Gastroenteritis can spread very easily, so you should wash your hands regularly while you're ill and stay off work or school until at least 48 hours after your symptoms have cleared, to reduce the risk of passing it on (see Preventing gastroenteritis).
When to get medical advice
You don't normally need to see your GP if you think you have gastroenteritis, as it should get better on its own.
Visiting your GP surgery can put others at risk, so it's best to call NHS 111 or your GP if you're concerned or feel you need advice.
Get medical advice if:
- you have symptoms of severe dehydration, such as persistent dizziness, only passing small amounts of urine or no urine at all, or if you're losing consciousness
- you have bloody diarrhoea
- you're vomiting constantly and are unable to keep down any fluids
- you have a fever over 38C (100.4F)
- your symptoms haven't started to improve after a few days
- in the last few weeks you've returned from a part of the world with poor sanitation
- you have a serious underlying condition, such as kidney disease, inflammatory bowel disease or a weak immune system, and have diarrhoea and vomiting
Your GP may suggest sending off a sample of your poo to a laboratory to check what's causing your symptoms. Antibiotics may be prescribed if this shows you have a bacterial infection.
Looking after a child with gastroenteritis
You can look after your child at home if they have diarrhoea and vomiting. There's not usually any specific treatment and your child should start feeling better in a few days.
You don't normally need to get medical advice unless their symptoms don't improve or there's a risk of a more serious problem (see Getting medical advice for your child).
To help ease your child's symptoms:
- Encourage them to drink plenty of fluids. They need to replace the fluids lost from vomiting and diarrhoea. Water is generally best. Avoid giving them fizzy drinks or fruit juice, as they can make their diarrhoea worse. Babies should continue to feed as usual, either with breast milk or other milk feeds.
- Make sure they get plenty of rest.
- Let your child eat if they're eating solids and feel hungry. Try small amounts of plain foods, such as soup, rice, pasta and bread.
- Give them paracetamol if they have an uncomfortable fever or aches and pains. Young children may find liquid paracetamol easier to swallow than tablets.
- Use special rehydration drinks made from sachets bought from pharmacies if they're dehydrated. Your GP or pharmacist can advise on how much to give your child. Don't give them antidiarrhoeal and anti-vomiting medication, unless advised to by your GP or pharmacist.
Babies and young children, especially if they're less than a year old, have a greater risk of becoming dehydrated. Read advice about looking after babies and children under five who have diarrhoea and vomiting.
Make sure you and your child wash your hands regularly while your child is ill and keep them away from school or nursery until at least 48 hours after their symptoms have cleared (see Preventing gastroenteritis).
Getting medical advice for your child
You don't usually need to see your GP if you think your child has gastroenteritis, as it should get better on its own, and taking them to a GP surgery can put others at risk.
Call NHS 111 or your GP if you're concerned about your child, or they:
- have symptoms of dehydration, such as passing less urine than normal, being unusually irritable or unresponsive, pale or mottled skin, or cold hands and feet
- have blood in their poo or green vomit
- are vomiting constantly and are unable to keep down any fluids or feeds
- have had diarrhoea for more than a week
- have been vomiting for three days or more
- have signs of a more serious illness, such as a high fever (over 38C or 100.4F), shortness of breath, rapid breathing, a stiff neck, a rash that doesn't fade when you roll a glass over it or a bulging fontanelle (the soft spot on a baby's head)
- have a serious underlying condition, such as inflammatory bowel disease or a weak immune system, and have diarrhoea and vomiting
Your GP may suggest sending off a sample of your child's poo to a laboratory to confirm what's causing their symptoms. Antibiotics may be prescribed if this shows they have a bacterial infection.
How gastroenteritis is spread
The bugs that cause gastroenteritis can spread very easily from person to person.
You can catch the infection if small particles of vomit or poo from an infected person get into your mouth, such as through:
- close contact with someone with gastroenteritis – they may breathe out small particles of vomit
- touching contaminated surfaces or objects
- eating contaminated food – this can happen if an infected person doesn't wash their hands before handling food, or you eat food that has been in contact with contaminated surfaces or objects, or hasn't been stored and cooked at the correct temperatures (read more about the causes of food poisoning)
A person with gastroenteritis is most infectious from when their symptoms start until 48 hours after all their symptoms have passed, although they may also be infectious for a short time before and after this.
It's not always possible to avoid getting gastroenteritis, but following the advice below can help stop it spreading:
- Stay off work, school or nursery until at least 48 hours after the symptoms have passed. You or your child should also avoid visiting anyone in hospital during this time.
- Ensure you and your child wash your hands frequently and thoroughly with soap and water, particularly after using the toilet and before preparing food. Don't rely on alcohol hand gels, as they're not always effective.
- Disinfect any surfaces or objects that could be contaminated. It's best to use a bleach-based household cleaner.
- Wash contaminated items of clothing or bedding separately on a hot wash.
- Don't share towels, flannels, cutlery or utensils while you or your child is ill.
- Flush away any poo or vomit in the toilet or potty and clean the surrounding area.
- Practice good food hygiene. Make sure food is properly refrigerated, always cook your food thoroughly, and never eat food that is past its use-by date – read more about preventing food poisoning.
Take extra care when travelling to parts of the world with poor sanitation, as you could pick up a stomach bug. For example, you may need to boil tap water before drinking it.
Young children can have the rotavirus vaccination when they’re two to three months old, which can reduce their risk of developing gastroenteritis.
Learn more about vomiting or diarrhoea: vomiting
Nausea (feeling sick) and vomiting (being sick) in adults isn't usually a sign of anything serious. In most cases, you won't need any specific treatment and can take care of yourself at home until you feel better.
One of the most common causes of vomiting in adults is a gut infection (gastroenteritis), which usually only lasts one or two days.
However, vomiting can occasionally be a sign of a more serious problem and may require emergency help.
Find separate information about vomiting in children and babies.
This topic covers:
When to get medical advice
Try to avoid going to your GP because if your vomiting is caused by an infection it can spread to others very easily.
If you're feeling very unwell or are worried about your vomiting, call your GP or NHS 111.
You should also get medical advice if:
- you've been vomiting repeatedly for more than 48 hours and it's not improving
- you're unable to keep down any fluids
- you have signs of severe dehydration – such as dizziness and passing little or no urine
- your vomit is green (this could mean you're bringing up bile, which suggests you may have a blockage in your bowel – see below)
- you've lost a lot of weight since you became ill
- you experience episodes of vomiting frequently
When to get emergency help
Call 999 for an ambulance, or go to your nearest hospital accident and emergency (A&E) if you also have:
- sudden, severe stomach pain – this may be a sign of appendicitis
- severe chest pain
- blood in your vomit or what looks like coffee granules
- a stiff neck and high temperature (fever)
- a sudden, severe headache that's unlike any headache you've had before
- diabetes and have been vomiting persistently – particularly if you need to take insulin
You should also get emergency help if you think you've swallowed something poisonous.
Looking after yourself at home
The most important thing you can do is to keep taking small sips of water so you don't become dehydrated.
A sweet drink such as fruit juice can be useful for replacing lost sugar, although you should avoid sweet drinks if they make you feel sick. Salty snacks, such as crisps, can help replace lost salt.
You may also find ginger helps to relieve your nausea and vomiting. This is available as supplements, or can be found in ginger biscuits and ginger tea. Check with your pharmacist or GP before using ginger supplements.
Common causes of vomiting in adults
The most common causes of nausea and vomiting in adults include:
- gastroenteritis – this is most likely to be the cause if you also have diarrhoea; read about treating gastroenteritis
- pregnancy – pregnant women often have nausea and vomiting during the early stages of pregnancy; read about morning sickness, including things you can do to help reduce your symptoms
- migraines – intense, throbbing headaches that last for a few hours to days at a time, read about treating migraines
- labyrinthitis – which also causes dizziness and a feeling of spinning (vertigo)
- motion sickness – nausea and vomiting associated with travelling
Vomiting in adults can also be caused by a number of other things, including:
Learn more about vomiting or diarrhoea: treatment for diarrhoea
Diarrhoea usually clears up without treatment after a few days, particularly if it's caused by an infection.
In children, diarrhoea usually passes within five to seven days and rarely lasts longer than two weeks.
In adults, diarrhoea usually improves within two to four days, although some infections can last a week or more.
While waiting for your diarrhoea to pass, you can ease your symptoms by following the advice outlined below.
It's important to drink plenty of fluids to avoid dehydration, particularly if you're also vomiting. Take frequent small sips of water.
Ideally, adults should drink a lot of liquids that contain water, salt and sugar. Examples are soup broth or water mixed with juice.
If you're drinking enough fluid, your urine will be light yellow or almost clear.
It's also very important for babies and small children not to become dehydrated. Give your child frequent sips of water, even if they're vomiting. A small amount is better than none.
Fruit juice or fizzy drinks should be avoided as they can make diarrhoea worse in children.
If you're breastfeeding or bottle feeding your baby and they have diarrhoea, you should continue to feed them as normal.
Contact your GP immediately if you or your child develop any symptoms of dehydration.
Oral rehydration solutions
Your GP or pharmacist may suggest using an oral rehydration solution (ORS) to prevent dehydration if you're at risk – for example, if you're frail or elderly. ORS can also be used to treat dehydration that has already occurred.
Rehydration solutions usually come in sachets available from your local pharmacist without a prescription. They are dissolved in water, and replace salt, glucose and other important minerals that are lost if you're dehydrated.
Your GP or pharmacist may recommend giving your child an ORS if they're dehydrated or at risk of becoming dehydrated.
The usual recommendation is for your child to drink an ORS each time they have an episode of diarrhoea. The amount they should drink will depend on their size and weight.
Your pharmacist can advise you about this. The manufacturer's instructions should also give information about the recommended dose.
You may be able to give your baby an ORS if they become dehydrated, but check with your GP, pharmacist or health visitor first.
Opinion is divided over when and what you should eat if you have diarrhoea. However, most experts agree you should eat solid food as soon as you feel able to. Eat small, light meals and avoid fatty or spicy foods.
Good examples are potatoes, rice, bananas, soup and boiled vegetables. Salty foods help the most.
You don't need to eat if you've lost your appetite, but you should continue to drink fluids and eat as soon as you feel able to.
If your child is dehydrated, don't give them any solid food until they have drunk enough fluids. Once they stop showing signs of dehydration, they can start eating their normal diet.
If your child isn't dehydrated, offer them their normal diet. If they refuse to eat, continue to give them fluids and wait until their appetite returns.
Antidiarrhoeal medicines may help reduce your diarrhoea and slightly shorten how long it lasts. However, they're not usually necessary.
Loperamide is the main antidiarrhoeal medicine used, as it has been shown to be effective and causes few side effects.
Loperamide slows down the muscle movements in your gut so more water is absorbed from your stools. This makes your stools firmer and they're passed less frequently.
An alternative to loperamide is a different type of antidiarrhoeal medicine called racecadotril, which works by reducing the amount of water produced by the small intestine.
Evidence suggests this medication may be as effective as loperamide for treating diarrhoea.
Some antidiarrhoeal medicines can be bought from a pharmacy without a prescription.
Check the patient information leaflet that comes with the medicine to find out whether it's suitable for you and what dose you should take. Ask your pharmacist for advice if you're unsure.
Don't take antidiarrhoeal medicines if there's blood or mucus in your stools or you have a high temperature (fever). Instead, you should contact your GP for advice.
Most antidiarrhoeal medicines shouldn't be given to children. Racecadotril can be used in children over three months old if it's combined with oral rehydration and the other measures mentioned above, although not all doctors recommend it.
Always read the patient information leaflet that comes with the medication to check if it's suitable and find out the correct dose. Children under 16 years of age shouldn't be given aspirin.
Treatment with antibiotics isn't recommended for diarrhoea if the cause is unknown. This is because antibiotics:
- won't work if the diarrhoea is caused by a virus
- can cause unpleasant side effects
- can become less effective at treating more serious conditions if they're repeatedly used to treat mild conditions
Antibiotics may be recommended if you have severe diarrhoea and a specific type of bacteria has been identified as the cause.
They may also be used if you have an underlying health problem, such as a weakened immune system.
Occasionally, hospital treatment may be needed to treat serious dehydration. Treatment involves administering fluids and nutrients directly into a vein (intravenously).
Treating the underlying cause
If you've been diagnosed with a specific condition that's causing your diarrhoea, treating this may help improve your symptoms.
- irritable bowel syndrome (IBS) can be treated with changes to your diet and medications – read more about treating IBS
- inflammatory bowel disease can be treated with medications that help reduce inflammation in the bowel
- coeliac disease can be treated by excluding foods containing gluten from your diet – read more about treating coeliac disease
- bile acid malabsorption can be treated with medication that helps stop bile building up in the digestive system
Read more about common causes of diarrhoea.
Probiotics are live bacteria and yeasts found in some yoghurts and food supplements.
There's some evidence that certain probiotics can slightly shorten a period of diarrhoea, although the evidence isn't yet strong enough to recommend taking them.
There's also evidence to suggest some probiotics may reduce your chances of developing diarrhoea after taking antibiotics.