Emergency advice

Help someone who’s vomiting or has diarrhoea:

  1. Reassure them.
  2. Get them to sit down.
  3. Encourage them to drink and eat plain food when they can.

What causes diarrhoea and vomiting?

Diarrhoea and vomiting are usually caused by irritation to the digestive system.

Vomiting and diarrhoea can occur separately or together, but both can cause the body to lose vital fluids and salts. The aim is to prevent dehydration by giving frequent sips of water, even if the casualty is vomiting.

Cleanliness and good hand hygiene help prevent the spread of infectious diarrhoea.

Signs and symptoms

Look for:

  • feeling sick
  • vomiting, and later diarrhoea
  • stomach pains
  • fever.

What to do

  1. Reassure the casualty. Get them to sit down and make sure they are comfortable. 

    • If the casualty is vomiting, give them a warm damp cloth to wipe their face and keep reassuring them. 
  2. When the casualty has stopped vomiting, give them sips of water or unsweetened fruit juice. You can also give them an oral rehydration solution.

  3. When the casualty is feeling hungry again, advise them to eat small amounts of foods that are easily digested, such as bread, pasta or potatoes for the first 24 hours.

    Paracetamol can be taken for mild abdominal pain.  Do not give aspirin to childen under 16 years.

    • The person should seek medical attention if:
    • the vomiting persists more than 24-48 hours
    • the diarrhoea persists more than 5 days
    • they become dehydrated - small amounts of very dark urine (dry nappies in small children)
    • there is blood with the diarrhoea
    • the abdominal pain is getting worse
    • if you are concerned about a casualty's condition, particularly if they are a child or older person.

    Call 999 or go to A&E if:

    • the vomit contains blood or looks like ground coffee
    • they have a stiff neck and pain when looking at bright lights
    • there is sudden onset of severe abdominal pain.

Related first aid advice

Food poisoning

Food poisoning can be caused by eating contaminated food, usually when it hasn't been cooked properly. Find out what to look for and what to do.

Swallowed poisons

Poisons are substances that can cause damage if too much is absorbed by the body. Swallowed poisons include chemicals, fungi and berries. Find out what to look for and what to do.

Alcohol poisoning

When someone drinks too much alcohol they can suffer from alcohol poisoning. Find out what to look for and what to do.

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