What is Diarrhea? Causes, Symptom & Effective Treatment Options

Diarrhoea is defined as the passage of abnormally loose or watery faeces, which occurs at increased frequency. Approximately 80% of adults experience acute diarrhoea at least annually, whereas approximately 50% of children experience it at least twice annually. Most adults with acute diarrhoea experience mild symptoms that resolve themselves in less than 48 hours without receiving specific treatment. The clinical presentation can be in a milder form or moderate, severe forms with too frequent watery stools with or without admixed blood and mucus. Black tarry faeces are sometimes indicating a graver underlying disease.

There are three classifications:

• Acute diarrhoea persists for either one or two days and represents the most common classification.
• Persistent diarrhoea exists for two to four weeks.
• Chronic diarrhoea exceeding four weeks' duration or recurring frequently over time suggests that an underlying condition exists that necessitates medical investigation.

Even though an infrequent episode of diarrhoea is rarely concerning, recurrent episodes or those persisting for an extended period of time should be evaluated with a healthcare provider.

Common Physical Indicators

The typical manifestation of diarrhoea is loose or watery stool. Additionally, patients may present with bloating or cramping of the abdomen, a sudden and immediate urge to defecate, and nausea. These manifestations are unpleasant yet relatively mild and therefore do not warrant a visit to a healthcare provider if they resolve in less than 72 hours.

Critical Signs of Dehydration in Adults and Children

Adults are susceptible to dehydration due to diarrhoea, especially in the elderly and immunocompromised populations. In adults, symptoms of dehydration consist of headaches, warm/dry skin, decreased/tea-coloured urine production, lightheadedness/fatigue despite adequate rest periods, and extreme nausea/vomiting. Associated high grade fever is also a warning sign requiring medical attention.

Children demonstrate similar warning signs of dehydration related to diarrhoea. Warning signs in children include fewer than six wet nappies per 24-hour interval for infants, no urination for eight hours in toddlers, no tearing upon crying and excessive irritability/confusion. Because dehydration can rapidly progress in children, it is imperative to contact a paediatrician immediately.

Severe Complications

Other symptoms accompanying diarrhoea are indicative of a more serious issue requiring professional assessment. Therefore, it is advisable to contact a healthcare provider if you have experienced fever, severe abdominal pain, vomiting, blood or mucus in the stool, and unintended weight loss. This may indicate an infectious process or underlying condition that may not resolve without appropriate therapy.

Infant Symptoms

Infants are at greater risk of developing dehydration secondary to diarrhoea than adult populations. OTC medications commonly prescribed for adults should never be administered to children; thus, consult a paediatrician prior to administering any treatment for your child's diarrhoea. A paediatrician can provide guidance on the safest methods to maintain hydration status in your child based on their age and via either breast milk/formula/electrolyte solutions in older children.

Diarrhoea is caused by numerous factors. The most prevalent cause of diarrhoea is a viral enteric infection, often termed "stomach virus" or "stomach flu". Norovirus is the most frequent cause of acute diarrhoea in adults, while rotavirus is the most frequent cause of acute diarrhoea in children.

Foodborne illnesses represent another common cause of diarrhoea. Foodborne illnesses develop when individuals eat contaminated food/drinks that contain pathogenic organisms/toxins. Traveller's diarrhoea develops when individuals ingest new bacterial pathogens in poorly sanitised environments.

Some medications can produce diarrhoea as a side effect. Disruption of normal intestinal flora occurs when taking antibiotics. Antacids containing magnesium, certain anticancer agents and excessive use of laxatives can all alter stool consistency.

Individuals who suffer from food intolerance, such as lactose intolerance/fructose malabsorption/coeliac disease, fail to adequately metabolise particular compounds, resulting in diarrhoea. Bowel diseases characterised by inflammation (e.g., Crohn's disease/ulcerative colitis) exhibit diarrhoea as one of their primary symptoms. Anxiety and stress exacerbate symptoms in patients with irritable bowel syndrome (IBS). Temporary disruption of nutrient absorption and bowel function post-bowel surgery can also produce diarrhoea.

For most instances of acute diarrhoea, management will involve resolution without medical intervention. Several approaches exist to alleviate your symptoms and expedite healing. Staying hydrated is the first and foremost method. Drink plenty of water and other fluid replacements with equal amounts of sodium/potassium (i.e., diluted fruit juices/low-sodium broths/sports drinks) to replenish lost electrolytes/fluids through your loose stools. The ideal is to take Oral Rehydration Solution (ORS) prepared with specific sodium-glucose ratio as advised by the WHO.

Consumption of bland foods that firm up stool can aid recovery. One common method involves adherence to the BRAT diet (bananas/rice/applesauce/toast); lean protein sources (chicken/fish/potatoes) are also suitable alternatives. Consume minimal amounts of caffeine/alcohol/dairy/gas-producing foods (beans/carbonated beverages) until symptoms subside. As food habits vary among adults and children, it is advisable to have a bland diet with gradual resumption of normal routine diet of that individual. It will be hugely beneficial to avoid dairy products during the acute phase of the illness, say the first 48-72 hours. High sugar fruit juices may sometimes cause osmotic diarrhoea.

A spoonful of sugar and a pinch of salt dissolved in 1 litre of water is a classic home-made basic ORS, until someone gets pharmacy access.

Symptomatic treatment for adults may include anti-diarrheals like loperamide and/or racecadotril and for children it is better to avoid anti-diarrheals and instead use anti-secretory agents like racecadotril to prevent fluid loss and control symptoms. Probiotic supplements may be suggested to assist in restoring normal intestinal flora, although you should discuss this option with your physician before adding any additional supplements. Having said that, totally avoid anti-diarrheals if the faeces show blood or mucus; seek immediate medical attention in such instances.

Although diarrhoea is unpredictable, you can minimise your chances of experiencing it. Handwashing with soap/water after defecation and before preparing/handling/consuming food reduces incidence. Proper food storage/temperature control/preparation (cook meat to the recommended internal temperature), avoiding consumption of expired food/drinks, avoiding tap water/ice/undercooked/raw meat/shellfish/products made from unpasteurised milk/juices while travelling, and limiting consumption of fresh fruits/vegetables while travelling to unsanitary regions protect you from consuming unknown pathogens. Administration of the rotavirus vaccine protects against one of the most common causes of acute diarrhoea in children; discuss administration with your healthcare provider.

Seek medical consultation if diarrhoea fails to improve after a few days, if you continue to experience repeated episodes of diarrhoea, or if your diarrhoea includes fever/severe abdominal pain/rectal bleeding/signs of dehydration. Patients diagnosed with chronic diarrhoea lasting >28 days should consult with a specialist regarding evaluation for potential underlying conditions (e.g., IBS/inflammatory bowel disease/coeliac disease). Early identification leads to better outcomes for your comfort level.

Diarrhoea is a very common affliction that virtually everyone will experience at least once. For the vast majority of affected persons, diarrhoea will be transient and easily managed at home with rest/hydration and/or dietary modifications. However, recognising the symptoms of dehydration, being aware of which stimuli elicit them, and understanding when to seek medical assistance are vital for maintaining optimal health.