Chronic Diarrhoea: Causes and Treatment Options

Chronic diarrhoea has numerous potential causes, ranging from infections and dietary factors to more serious underlying conditions.

Dr Aamir Sajjad, esteemed consultant gastroenterologist, provides an expert insight into the causes and treatment of chronic diarrhoea.

What is defined as chronic diarrhoea?

Chronic diarrhoea is diagnosed when diarrhoea persists for 4 weeks or longer. This can be either continuous, occurring daily or intermittent, with episodes coming and going over time.

Importantly, chronic diarrhoea is a symptom of an underlying condition, rather than a disease on its own. It can be accompanied by additional symptoms such as abdominal pain, bloating, weight loss, fatigue or dehydration, depending on the cause.

What can cause chronic diarrhoea?

Chronic diarrhoea has a wide range of potential causes, including:

Digestive disorders

Irritable bowel syndrome (IBS): A functional gastrointestinal disorder that can cause chronic diarrhoea, often accompanied by abdominal pain and bloating.
Inflammatory bowel disease (IBD): Conditions like Crohn’s disease and ulcerative colitis cause inflammation of the gastrointestinal tract, leading to chronic diarrhoea, abdominal pain and weight loss.
Coeliac disease: An autoimmune reaction to gluten that can damage the small intestine and result in malabsorption, causing chronic diarrhoea.

Infections and post-infectious syndromes

Certain infections, particularly those caused by parasites, bacteria or viruses, can lead to chronic diarrhoea if left untreated or if post-infectious symptoms persist. Examples include Giardia lambia and Clostridium difficile infections.

Medications and supplements

Chronic diarrhoea can sometimes be a side effect of long-term use of certain medications such as antibiotics, laxatives or certain chemotherapy drugs. Overuse of supplements, especially magnesium, can also be a contributing factor.

Endocrine disorders

Hormonal imbalances, such as hyperthyroidism or diabetes-related autonomic neuropathy can disrupt normal bowel function, leading to chronic diarrhoea.

Cancer

While less common, chronic diarrhoea can be a symptom of certain types of cancer, such as colorectal cancer, pancreatic cancer or neuroendocrine tumours, including carcinoid syndrome. Blood in the stool, significant weight loss or severe fatigue accompanying diarrhoea warrants prompt medical evaluation to rule out malignancy.

How is chronic diarrhoea treated?

Treatment of chronic diarrhoea depends on its underlying cause. Your gastroenterologist will begin with a detailed medical history, physical examination and diagnostic tests, which may include stool analysis, blood tests, imaging studies or endoscopy.

For infections, treatment will involve antibiotics, antivirals or antiparasitic medications. In cases of IBS or IBD, a tailored treatment plan will be created, including anti-inflammatory medications, biologic therapies or dietary modifications. Coeliac disease management involves lifelong adherence to a gluten-free diet.

For chronic diarrhoea linked to medications, adjusting dosages or switching to alternative medications will resolve the issue. Similarly, addressing hormonal imbalances in endocrine disorders such as with hormone replacement therapy can lead to improvement.

In cases of cancer, treatment will focus on managing both the chronic diarrhoea and the cancer itself, which may involve surgery, chemotherapy or radiotherapy.

Can lifestyle changes help manage chronic diarrhoea?

Lifestyle changes can play a significant role in managing chronic diarrhoea and improving overall quality of life.

Dietary adjustments are often the first step. Identifying and avoiding trigger foods, such as spicy dishes, high-fat meals, alcohol and artificial sweeteners, can help reduce symptoms. Maintaining a balanced diet with adequate fibre intake is crucial; soluble fibre sources like oats and bananas can help regulate bowel movements.

Chronic diarrhoea can result in dehydration and imbalances in electrolytes. For this reason, staying hydrated by drinking plenty of water and incorporating oral rehydration solutions is vital. Probiotics, which are beneficial bacteria found in supplements or fermented foods, can also support gut health and reduce diarrhoea in some cases.

Often, chronic diarrhoea is exacerbated by stress, especially in conditions like IBS. Stress management techniques such as mindfulness, yoga and cognitive behavioural therapy can address the psychological factors and improve gut health at the same time.

Similarly, avoiding alcohol and smoking is advisable, as these substances can irritate the gastrointestinal tract and exacerbate symptoms. Regular physical activity further supports overall digestive health and reduces stress.

To book an appointment with Dr Sajjad, head on over to his Top Doctors profile today.