Diarrhoea is defined as an increase in stool frequency accompanied by a decrease in consistency. It is not a common side effect of head and neck cancer, but it can sometimes appear after chemotherapy or the administration of certain drugs or antibiotics. It is usually occasional and lasts only a few days. If it is prolonged, consult your medical team.


Because diarrhoea can lead to dehydration, drink plenty of fluids (water, herbal teas, weak broths, low-sugar isotonic drinks) in small sips throughout the day.

Homemade isotonic drink: Mix the juice of two lemons, a tablespoon of honey, a dessert spoon of sea salt and a dessert spoon of bicarbonate of soda in a litre of water. When these ingredients are dissolved, leave it in the fridge until it is cool.

Have small servings of food frequently throughout the day.

Start with a liquid diet, e.g., rice water, and once well-tolerated, incorporate easily digestible foods such as mashed potatoes and carrots, boiled rice, white fish, or boiled chicken and baked or grated apples.

Toasted bread, breadsticks, meat, fish, eggs (French omelette, grilled chicken, fish en papillote), pasta, rice and rice soups, potatoes, wheat and tapioca, biscuit, crackers, etc.

Boiling, grilling, steaming, and baking in the oven are easier-to-digest cooking methods.

  • Wholegrain cereals and derivatives, raw fruits, vegetables, pulses, and nuts are not recommended.
  • Choose fruit without skin, baked in the oven or microwave, or preserved in juice, syrup, or strained juices. Fruit in syrup (such as apple, pear, and peach), quince or banana and well-ripened pear are good options.

Some suggested recipes:

  • Vegetables low in fibre can be consumed in small quantities (test tolerance) always without skin and seeds and very well cooked, also in the form of strained soups or broths.
  • Test fruit and vegetable smoothies’ tolerance as all fibre is removed in the process

Butter, margarine, lard, mayonnaise, cream, heavy cream, and baked goods, amongst others, are not recommended.

Depending on tolerance, they can be gradually incorporated.

Avoid coffee, chocolate, black tea, alcohol, and irritating and spicy condiments such as pepper.

Sweets, fruit nectar, simple sugar or honey, chocolate, sweetened or sweetened drinks, xylitol, sorbitol, etc. are not recommended.