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Understanding Diarrhoea

Many people have problems with diarrhoea, not everyone knows why.

Get back in rhythm

Your digestive system has a natural rhythm, which is usually steady and regular, constantly working to provide your body with the nutrients it needs. When something upsets the natural balance in your intestines, your digestive system can become irritated and starts to work too fast. The result can be diarrhoea. That can leave your body feeling out of tune. Luckily there are plenty of things you can do to help get back in rhythm again.

Why diarrhoea happens

When your digestive system is working in its normal rhythm, food and fluid pass regularly from the stomach into the small intestine, food is then broken down and the nutrients absorbed along with most of the fluid. The remaining waste and some water then pass into the colon (large intestine), where more water is absorbed and finally the waste is passed in the form of stools. When the cells in your small intestine or colon become irritated, the relaxed and regular movement of your intestines can become overactive. Essential salts and fluids end up being passed through the colon too quickly and aren’t absorbed by the body.

The result of this is loose or watery stools, commonly known as diarrhoea. Everyone is familiar with the occasional bout of diarrhoea, but some people suffer more frequently. It can be difficult to live with and the effects are emotional as well as physical.

Main causes of frequent and occasional diarrhoea

When you get diarrhoea, it means loose or watery stools, and people can often experience abdominal pain, cramps and bloating too. Most people only experience diarrhoea from time to time, but some people can get diarrhoea rather more frequently. Typically episodes of diarrhoea clear up within a few days, but can last longer. Longer lasting or persistently recurrent diarrhoea can indicate an underlying medical condition, so you may need to consult your doctor.


  • If diarrhoea persists beyond 48 hours seek medical advice as soon as possible.
  • Fluid and electrolyte depletion may occur when suffering diarrhoea.
  • If dehydration is suspected seek medical attention.
  • Check with your employer before returning to work to avoid putting others at risk.
  • Maintain good hand hygiene by regular washing or use of a hand sanitiser.

Other types of diarrhoea

To help you understand your body better, here are some of the common types of diarrhoea:

  • Travellers’ diarrhoea: when you’re abroad it’s easy to get foreign bugs or food poisoning.
  • Infectious: unfortunately, there are numerous infections that can lead to diarrhoea.
  • Diarrhoea and pregnancy: an unwanted problem that sometime accompanies pregnancy**.
  • Norovirus: If you catch the Winter Vomiting Bug, it’s likely diarrhoea will be a symptom.
  • Diarrhoea in children: Unfortunately a common problem for kids*, as they are less immune to some of the bugs we encounter in everyday life.

* Imodium cannot be used in children under 12 years of age.
** If you experience diarrhoea during pregnancy consult your healthcare professional.



Manage your lifestyle

Follow these tips to help you improve your digestive health and get your life back in rhythm.



IMODIUM® has been helping diarrhoea sufferers globally for 40 years. Get quick answers to common questions and advice on key diarrhoea related topics.