Diarrhoea
Chemotherapy-induced diarrhoea (CID) affects up to 80% of patients on certain drugs (5-FU, irinotecan, capecitabine). Radiation to the pelvic or abdominal area also causes diarrhoea. Severe diarrhoea causes dangerous dehydration and electrolyte loss and may require dose delays or hospitalisation.
Herbs & Supplements — Safety Information
Herbal information is for educational purposes. Many herbs interact with chemotherapy and other medications — consult your oncologist before use.
When to Seek Medical Help Immediately
- •More than 6 watery stools per day
- •Blood or mucus in stool
- •Fever with diarrhoea — signs of infection
- •Signs of dehydration — dry mouth, no urination, dizziness
- •Diarrhoea after irinotecan (CPT-11) — can be severe and require loperamide plus atropine
5 Natural Remedies
Oral Rehydration Solution (ORS)
Best for: Any cause of diarrhoea, rehydration during active episodes
Replacing lost fluids and electrolytes is the single most important intervention in diarrhoea management. A homemade ORS closely matches the WHO formula and is more effective than plain water at rehydrating because it uses glucose to drive sodium (and water) absorption in the intestine.
🧪 How to Prepare
Mix in 1 litre of boiled (then cooled) water: 6 level teaspoons of sugar (or honey), ½ level teaspoon of salt. Stir well until dissolved. Optional: add the juice of ½ lemon for potassium. Alternatively, coconut water is a natural electrolyte solution.
⏰ When to Take
Sip 200–300ml after every loose stool. Aim for at least 2 litres of fluid per day total. Room temperature fluids are better tolerated than ice-cold.
BRAT Diet
Best for: Active diarrhoea episodes, post-chemo diarrhoea days
Bananas provide potassium and pectin (a soluble fibre that helps firm stools). Rice is low-residue and easy to digest. Applesauce provides pectin. Toast provides easily digestible carbohydrate. Together they reduce intestinal motility and stool water content.
🧪 How to Prepare
Plain white rice (well-cooked), ripe bananas, unsweetened applesauce, plain white toast (no butter). Also include: boiled potatoes, plain crackers, cooked carrots, clear broths. Advance to a normal diet as diarrhoea resolves.
⏰ When to Take
For 24–48 hours during active diarrhoea episodes. Advance diet gradually.
Probiotics (Lactobacillus & Bifidobacterium)
Best for: Prevention and treatment of chemo-related gut dysbiosis and diarrhoea
Chemotherapy disrupts the gut microbiome, often causing dysbiosis that worsens diarrhoea. Evidence-based probiotic strains — particularly Lactobacillus rhamnosus GG and Bifidobacterium lactis — help restore healthy gut flora and reduce the severity and duration of chemotherapy-induced diarrhoea.
🧪 How to Prepare
Choose a multi-strain probiotic with at least 10 billion CFU per dose. Lactobacillus rhamnosus GG (Culturelle) has the most clinical trial data. Food sources: plain yoghurt with live cultures, kefir, miso soup (if not contraindicated).
⏰ When to Take
Daily, preferably with food. Space at least 2 hours from antibiotics if taking them. Best started prophylactically rather than after diarrhoea begins.
Active compound: Live bacterial cultures (Lactobacillus, Bifidobacterium strains)
Psyllium Husk (Soluble Fibre)
Best for: Loose stools with urgency, radiation-induced diarrhoea
Psyllium forms a gel in the intestines that absorbs excess water from loose stools, adding bulk and slowing transit time. It is one of the most effective non-drug treatments for diarrhoea-predominant bowel conditions and is safe alongside cancer treatments.
🧪 How to Prepare
1 teaspoon of psyllium husk powder in a full glass of water. Drink immediately before it gels. Then drink another glass of water.
⏰ When to Take
1–2 times daily. Introduce gradually — start with ½ tsp.
Coconut Water
Best for: Rehydration, electrolyte replacement during diarrhoea
Natural coconut water provides potassium, sodium, and magnesium in ratios close to a natural electrolyte drink. It is gentle on the gut, easy to drink when nauseous, and helps maintain hydration without the high sugar content of commercial sports drinks.
🧪 How to Prepare
Drink plain, unsweetened coconut water (refrigerated is most palatable). Fresh coconut water is ideal — packaged is acceptable. Avoid coconut water with added sugars or flavourings.
⏰ When to Take
200–300ml after each loose stool. Throughout the day alongside other fluids.
Evidence Level Guide