Diarrhoea is when you (or a family member) have to keep going to the toilet to pass loose, watery bowel motions (‘poos’).
What causes diarrhoea
Travel to new areas may cause an upset stomach (eg, from contaminated food or water).
Brief diarrhoea can result from infections or a reaction to some medicines.
Mild diarrhoea can result from an alcohol binge, emotional stress, an intolerance to certain foods, or food poisoning.
Chronic diarrhoea can indicate medical problems, such as:
- Crohn's disease
- colon cancer
- intolerance to milk or wheat products
- irritable bowel syndrome
- malabsorption syndrome.
See your doctor if you’re worried about any of these.
Diarrhoea involves frequent, loose bowel motions (‘poos’).
With some types of diarrhoea you might feel you have to get to the toilet urgently – and your bowel motion might be explosive.
Diarrhoea is usually mild and doesn’t last long – but it may be a symptom of a disease in your intestine or stomach.
Along with the diarrhoea, you might also have:
- abdominal pain and cramping
- change in the colour of your motions
- mucous, pus, blood or fat in the motions
- a feeling of weakness.
- Diarrhoea usually gets better in a day or two. If you have stomach cramps, try a hot water bottle or wheat pack on your tummy, or take paracetamol (such as Panadol).
- If you or your child has a rash (like a nappy rash) from the diarrhoea, use zinc and castor oil ointment or a barrier cream. Make sure the skin is clean and dry before you apply this.
- Some painkillers (called NSAID – such as aspirin, ibuprofen, diclofenac) can cause diarrhoea – so don’t take these when you have it.
- There are medicines that stop diarrhoea (like Imodium) – but in doing this they also stop your body from getting rid of the bacteria or virus that has caused the diarrhoea. They can also cause a blockage in your bowel, so it is best to avoid using them unless you really can't cope with the diarrhoea.
Long periods of diarrhoea, or repeated episodes, can lead to dehydration, which can be dangerous.
- There is a greater risk of dehydration when diarrhoea and vomiting occur at the same time.
- Those most at risk are infants, children and older people.
If you or a family member is dehydrated, the main signs will be:
- very little (or no) urine being passed
- the urine being very dark and smelly.
A useful test is to pinch some skin on your tummy or inner thigh. If it stays in the pinched shape after you let go, that is a clear sign of dehydration.
Infants (up to 1 year)
If your baby is dehydrated, this is what to do:
- Start with clear fluids or a rehydration drink such as Pedialyte or Gastrolyte.
- Alternate feeds of rehydration solution with breast milk or formula.
- Go back to your baby’s normal diet as soon as they have no signs of dehydration (they’re passing urine and their skin relaxes when pinched). This will help them recover more quickly and not lose as much weight. If your baby eats solids, start off with starchy foods such as baby rice, bread, mashed potatoes and bananas.
Children and adults
If you or your child is dehydrated, this is what to do:
- Start with clear fluids, such as water, clear soup or a rehydration drink like Gastrolyte or Pedialyte. You can also use sports drinks containing electrolytes, such as Powerade, diluted 50/50 with water. (Try freezing the rehydration drink into iceblocks if your child doesn’t like the taste.)
- Adults should aim for 2–3 litres of fluid a day (unless your doctor has told you to restrict fluids for some reason).
- Avoid drinks containing a lot of sugar (like soft drinks) because they can make your diarrhoea worse. Diluted apple juice is OK, but no other fruit juices.
- Avoid foods that are high in fibre (like bran), whole fruits (except bananas) and vegetables, spicy or fatty foods, alcohol, and caffeinated drinks (like coffee or tea).
- Eat starchy foods that are easily absorbed – such as bread, crackers, rice, pasta, noodles and mashed potatoes. Chicken (with the skin removed) and bananas are also good.
When to see your doctor
See your doctor if:
- there is any blood, pus or mucous in your bowel motions
- you develop a rash
- the diarrhoea lasts more than 1 week or comes back
- you get any new or worse symptoms.
You must also see your doctor if you (or a family member) are badly dehydrated. The signs include:
- little or no urine passed in the last 8 hours and the urine is dark and smelly
- reduced saliva in the mouth, no tears, sunken eyes, sunken fontanelle in infants
- dizziness, lethargy (no energy), floppiness, rapid heart rate and breathing, cool hands and feet (or grey cold skin)
- skin does not relax after being pinched.
Call Healthline 0800 611 116 if you are unsure what you should do.
This helps prevent the spread of viruses and bacteria that can cause diarrhoea. Always wash your hands thoroughly after using the toilet and changing nappies, and before meals.
Following some simple rules can reduce the bacteria that cause diarrhoea.
- Always put foods that could spoil in the fridge.
- Cook meat thoroughly.
- Never put cooked meat on surfaces or plates that have held raw meat.
- Wash chopping boards with hot water and soap.
- Disinfect bench tops, stovetops and boards with a diluted bleach solution.