Understanding Diarrhoea

Diarrhoea is a common condition characterised by loose, watery stools occurring more frequently than usual.  While often mild and short-lived, it can sometimes signal an underlying health issue or lead to complications such as dehydration.  As most people experience diarrhoea at some point in their lives, understanding its causes, management and the actions that may help with prevention, is important for better health.

What is diarrhoea?

Diarrhoea refers to the passage of three or more loose or liquid stools per day.  It occurs when the intestines are unable to properly absorb water or nutrients, or when they actively secrete excessive fluid.

Common causes

Diarrhoea can result from a wide variety of factors.  These include:

• From infections, such as viruses, bacteria (E. coli, Salmonella, Campylobacter) and parasites, particularly Giardia lamblia.  These are typically spread through contaminated food, water or close contact with infected individuals.
• Food-related causes including food poisoning, food intolerances such as lactose intolerance and various food allergies.
• Certain medications including antibiotics that disrupt the balance of gut bacteria, magnesium-containing antacids and some cancer treatments may contribute as well.
• Digestive disorders such as irritable bowel syndrome (IBS), inflammatory bowel disease including Crohn's disease and ulcerative colitis, coeliac disease and pancreatic insufficiency are additional underlying causes. 
• Emotional stress and anxiety.
• Lifestyle factors, including high intake of caffeine and alcohol or spicy foods can further increase the likelihood of experiencing diarrhoea. 
• Additionally, individuals with weakened immune systems are more likely to experience prolonged or persistent diarrhoea following an episode of gastroenteritis. 

Symptoms

Symptoms of diarrhoea are more than frequent loose or watery stools.  Many people also experience abdominal cramps, an urgent need to use the toilet, bloating, nausea or vomiting and sometimes fever when an infection is present. 

A major concern is dehydration, which can develop quickly and may present with warning signs such as a dry mouth, excessive thirst, dizziness, reduced or infrequent urination and dark yellow urine.  In infants, dehydration may appear as sunken eyes or a sunken soft spot on the head, along with fewer than usual wet diapers.

When to get help:  If diarrhoea symptoms worsen or persist for more than two days in an adult, it is important to seek medical attention.  The guidelines published by the TGA in Australia are:

Management

Effective management of diarrhoea begins with rehydration, which is a crucial step for preventing complications.  Drinking plenty of water, clear fluids and broths, helps replace lost fluids.  Oral rehydration solutions such as sports or electrolyte-containing drinks are ideal, because they restore vital salts and electrolytes that are depleted through frequent stools. 

Alongside rehydration, dietary adjustments play an important role in soothing the digestive system.  Bland, easy-to-digest foods such as bananas, rice, plain toast and potatoes, help rest the gut, while fatty, greasy, spicy foods, as well as caffeine and alcohol, should be avoided until symptoms settle to prevent further irritation.

Nutritional and herbal supplements can also support recovery.  Certain probiotic strains, including Lactobacillus rhamnosus GG and Saccharomyces boulardii, have been shown to help reduce both the duration and severity of diarrhoea, by restoring healthy gut flora.  Soluble fibre supplements such as psyllium husk can absorb excess fluid and promote well-formed stools.  Also, zinc, particularly in the form of zinc carnosine, helps strengthen the intestinal barrier and support immune function, aiding faster recovery.

Herbal medicine can offer additional gentle support including Ginger (Zingiber officinale) which eases nausea and gut spasming due to its anti-inflammatory and calming properties.  Peppermint (Mentha × piperita) acts as a natural antispasmodic that can reduce stomach cramping and Chamomile (Chamomilla recutita) provides mild anti-inflammatory effects that soothe irritated intestinal tissue.  Demulcent herbs like Hoheria (Hoheria populnea) and Marshmallow root (Althaea officinalis) form a protective mucilage that coats and calms the digestive lining.  New Zealand native Koromiko (Hebe stricta) is a powerful anti-diarrhoeal herb that soothes the digestive system.  Koromiko was shipped to Māori troops during World War ll in the Middle East for managing diarrhoea.

While these herbs and supplements can be supportive for mild cases, they may not be suitable for everyone and can interact with certain medications.  Therefore, they should be used cautiously and ideally under guidance from a health professional, particularly if symptoms persist or worsen.

Top tip: Kiwiherb Kawakawa Stomach Calm is a potent herbal formula that can support acute bouts of diarrhoea by soothing abdominal cramping and pain.  This product is made from New Zealand native honey and Kawakawa leaves, with Ginger and Peppermint making it ideal for digestive support.

Prevention

Prevention of diarrhoea relies on good hygiene, safe food habits and sensible precautions when travelling.  Washing hands thoroughly with soap and water and using hand sanitiser when soap isn’t available helps stop the spread of germs that commonly cause diarrhoea. 

Safe food practices are also important.  Cooking meat thoroughly, avoiding raw or unpasteurised dairy products, keeping raw and cooked foods separate and ensuring you drink clean, treated water help. 

When travelling in high-risk areas, additional care is needed.  Avoid tap water and ice, choose foods that are hot and freshly cooked and opt for fruits you can peel yourself to reduce exposure to contaminated surfaces or water.

Conclusion

Diarrhoea is a common but a manageable condition that can affect everyone at any age.  While most cases are mild and short-lived, and managed effectively by the body, understanding its causes, recognising symptoms and taking prompt action, are key to preventing complications such as dehydration. 

Effective management combines rehydration, gentle dietary choices and supportive supplements or herbal remedies.  In addition, practising good hygiene, following safe food practices and taking precautions during travel can significantly reduce the risk of developing or prolonging diarrhoea. 

By staying proactive, individuals can recover quickly, protect their overall health and minimise the likelihood of recurrence.