Generally, the stools passed by someone experiencing diarrhoea are between Type 5 and Type 7 on the Bristol Stool Chart.
Diarrhoea is when more than three loose, watery stools are passed within one day (Healthdirect 2019a).
Generally, the stools passed by someone experiencing diarrhoea are between Type 5 and Type 7 on the Bristol Stool Chart (Continence Foundation of Australia 2020).
Diarrhoea may be either:
Acute, lasting for up to two weeks (but generally resolving on its own within 1 to 2 days), or
Chronic, lasting for over four weeks.
(Better Health Channel 2015)
Diarrhoea is a common condition that generally doesn’t indicate a serious underlying issue. However, it can be an uncomfortable and unpleasant experience (NHS Inform 2020).
It is common for adults to experience one episode of acute diarrhoea every year (MedlinePlus 2016).
The Physiology of Diarrhoea
During the digestion process, the small and large intestines absorb nutrients and fluid from food that has been consumed (Bladder & Bowel Community 2021). The remaining substance then becomes waste (faeces) and is excreted. Generally, stools are between 60 and 90% water (Gotfried 2020).
Diarrhoea occurs when less fluid than usual is absorbed from the waste, or there is an increased fluid secretion from the intestines (Gotfried 2020).
Causes of Diarrhoea
Acute Diarrhoea
Most cases of acute diarrhoea are caused by infections such as gastroenteritis (Nemeth & Pfleghaar 2020). Potential pathogens include:
Damage to the intestinal epithelium (e.g. from radiotherapy or medicines)
Damage to the intestines due to decreased blood supply (e.g. from a hernia).
(Healthdirect 2019b)
It is estimated that one-fifth of all infectious diarrhoea cases are caused by norovirus.
Chronic Diarrhoea
Chronic diarrhoea may be caused by:
Lactose intolerance
Irritable bowel syndrome (IBS)
Coeliac disease
Crohn’s disease
Cystic fibrosis
Diabetes
Diverticular disease
Microscopic colitis
Chronic pancreatitis
Ulcerative colitis
Bowel cancer
Bile acid malabsorption
Having a gastrectomy
Having bowel surgery
As a side effect from chemotherapy.
(Healthdirect 2019b; NHS Inform 2020)
Types of Diarrhoea
Diarrhoea can be classified into different categories depending on the reason why excess fluid is present in the stool. These include:
Type of Diarrhoea
Description
Causes
Rapid passage of stool
Occurs when the stool exits the large intestine too early, causing a watery consistency
Overactive thyroid (e.g. hyperthyroidism)
Certain surgical procedures (e.g. removal of part of the stomach, small intestine or large intestine)
Inflammatory bowel disease
Caffeine
Certain medicines (e.g. laxatives)
Food high in sugar
Food intolerance
Anxiety and stress
Osmotic diarrhoea
Occurs when a substance cannot be absorbed and remains in the intestine, creating excess fluid
Certain food (e.g. some fruits and beans)
Sugar substitutes
Lollies and chewing gum
Lactose intolerance
Antibiotics
Secretory diarrhoea
Occurs when fluid and salts are secreted into the stool by the intestines
Infection
Certain laxatives
Certain rare tumours
Certain polyps
Inflammatory diarrhoea
Caused by inflammation of the epithelium in the large intestine, which results in proteins, blood, mucus and other fluids being released into the stool
Ulcerative colitis
Crohn’s disease
Tuberculosis
Certain cancers (e.g. lymphoma)
Malabsorption
Occurs when oil or grease is present in the stool due to inadequate absorption of nutrients
Certain disorders (e.g. Coeliac disease, Crohn’s disease)
Removal of part of the small intestine
(Gotfried 2020; Ruiz Jr 2021)
Symptoms of Diarrhoea
Diarrhoea may be associated with other symptoms including:
Diarrhoea can cause excess fluid loss, which may result in dehydration (NHS Inform 2020). This has the potential to be serious, particularly in older adults (Healthdirect 2019a).
Ensure that clients experiencing diarrhoea stay hydrated.
In most cases, acute diarrhoea will resolve on its own without treatment, especially if it is infection-related (NHS Inform 2020).
While the client recovers, you will need to manage their symptoms. You should:
Encourage the client to get plenty of rest
Maintain effective hygiene practices (if the diarrhoea is infection-related) to ensure that the infection does not spread
Ensure the client stays hydrated. Consider giving water or oral rehydration fluids
Administer medicines if clinically appropriate
Encourage the client to eat small, light meals as soon as they feel able to
Avoid giving fatty or spicy foods
Make short-term dietary adjustments as their intestines recover:
Avoid giving alcohol and fatty, sweet or spicy foods
Encourage consumption of starchy foods and yoghurt
Treat any underlying causes (e.g. IBS, coeliac disease).
(Healthdirect 2019a; NHS Inform 2020; Better Health Channel 2015)
If the client is severely dehydrated, they may require intravenous fluid therapy (NHS Inform 2020).
If diarrhoea is a long-term issue for the client, you may need to consider dietary changes. Consult a dietician for advice and investigate any underlying causes (Continence Foundation of Australia 2020).
Preventing Diarrhoea
The best way to prevent diarrhoea is to maintain effective hygiene practices, as this will reduce the risk of spreading infections that cause these symptoms (Healthdirect 2019a).
Refer to the following articles for comprehensive information on maintaining effective hygiene:
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