Indigestion - 
diet and lifestyle tips


Receive our quarterly lifestyle research updates

Indigestion is a feeling of discomfort or pain within the lower chest or abdomen caused by gastric acid irritation within the upper part of the gut namely the oesophagus, stomach or duodenum.  For other causes of abdominal pain  see - "indigestion" but the usual types of indigestion are:-

Heart burn. A burning feeling in the centre of the chest, sometimes combined with an acid taste in the back of the mouth. Usually made worse by eating a large meal, straining or leaning forward. This is caused by acid from the stomach refluxing back into the gullet.  

Classic indigestion comes on shortly after food and is a described as an intermittent burning discomfort in the top of the abdomen. Often helped temporarily by antacid medication (white medicine).   Caused by irritation of the stomach wall (gastritis or an ulcer).  If discomfort starts on an empty stomach (or starts in the middle of the night) it is more likely because of an ulcer or irritation of the section of gut which immediately follows the stomach called the duodenum. 

Indigestion and more often heart burn are common complaints experienced during chemotherapy or after surgery. The cause of pain is stomach acid, the acid that helps to digest your food. Stomach acid flows up Normally when you eat, food travels from your mouth down the esophagus through the lower esophageal sphincter. If thereís too much acid, or if the sphincter doesnít work properly, food and stomach acid can flow up or reflux into the oesophagus. Acid reflux irritates the lining of the oesophagus causing ulceration and often causes heartburn. If left long enough this can lead to bleeding or stricture formation (causing food to stick in the throat). The steroids or anti-inflammatory drugs often given during chemotherapy can also aggravate indigestion. If marked then further investigation is required and treatments with anti-acids or other drugs.  

The following manoeuvres may be helpful:

Diet suggestions and foods to avoid:

  • Do not overeat and eat slowly

  • Coffee and alcohol

  • Carbonated drinks (with and without caffeine) 

  • Fried food or foods high in fat

  • Pickled foods

  • Acidic foods such as citrus, onions and tomatoes, if these set off your heartburn.

  • Fruit should not necessarily be avoided unless they trigger your discomfort but eat the whole fruit and a avoid processed juices as these are more acidic

  • Peppermint and chocolate

  • Foods that you have discovered trigger your heartburn

  • Eat regularly, try not to miss meals

  • Small and frequent meals or snacks may be better tolerated

  • Do not eat large meals, especially late at night

Lifestyle changes:

  • Avoid straining if constipated or lifting

  • Allow two to three hours to pass after eating before you lie down.

  • Raise the head of your bed (eg with two bricks) so that chest is higher than your feet.

  • Wear looser-fitting clothing.

  • Lose weight, if you are overweight.

  • Wait at least two hours after eating before exercising.

  • When exercising breath out slowly when straining the stomach or lifting.

  • Gentle running is better than weight lifting.

  • If swimming learn to breath well as there is a tendency to hold the breath and strain, particularly with breast stroke.

  • Keep a heartburn journal to track foods or activities that aggravate your symptoms

Other types of abdominal discomfort:


  • If discomfort starts on an empty stomach (several hours after food) it is more likely because of an ulcer or irritation of the section of gut which immediately follows the stomach called the duodenum. The steroids which are given with chemotherapy often make this symptom worse or even bring it on in patients who have not previously experienced it. Often medication is prescribed to prevent this symptom - click on the headings in the adjacent column and also see  diet & indigestion.


  • Interference in the function of the small bowel often leads the colicky pain. This means the pain, usually in the centre of the abdomen, start slowly then build up into a severe spasm then quite quickly resolve only to build up gradually again. This is not usually caused by steroids and may indicate partial obstruction of the small bowel by tumour or fibrous bands caused by previous abdominal surgery.


  • Associated with constipation. This is mainly constant on the left lower side of the abdomen, if severe there may be some mild colicky type pains. There are several reasons why constipation may develop.

    Drugs - Pain killers including morphine, codeine, dihydrocodeine

    Antisickess medication given with chemotherapy and often cause constipation for the first 1-5 days. These include ondansetron and granisetron. It may be appropriate to take laxatives to prevent constipation on subsequent cycles of chemotherapy.

    Several laxatives are available from the clinic, GP or over the counter. A change in the diet may be helpful see diet & constipation.
  • Associated with diarrhoea. This is often associated with a discomfort in the lower abdomen. If severe it may be associated with colicky pains described above.

    A number of drugs are available for diarrhoea including Codeine and loperamide although a change in diet may help - see diet & diarrhoea


A feeling of fullness in the back passage. May be associated with a blood on the stool or a mucous discharge form the back passage. Often caused by radiotherapy to the lower pelvis can be help with suppositories  such as xyloproct or scheriproct - ask your doctor.

Drug therapy


Zantac (ranitidine) decreases the production of acid from the lining of the stomach.  This protects the stomach, oesophagus and duodenum from irritation and ulceration. It works by blocking a receptor in the stomach call the H2 receptor of the gastric parietal cell - so called H2 antagonist. A tablet containing 150mg of ranitidine twice a day (morning and evening). It doesn't matter exactly what times of day you take it but many people try to take it at the same times each day so its easier to remember. If you forget to take your tablet donít panic but  try not to miss more than one or two tablets in a row. Zantac is generally very well tolerated. Side effects are rare but include headache and  skin rashes Very rarely breast tenderness in men may occur.

Zoton (Lansoprazole), Protium (pantoprazole) or Losec (omeprazole) are very successful in treating the symptoms caused by acid irritation. Even if you don't already have indigestion it is useful to give Zoton to prevent these symptoms developing when steroids are given with chemotherapy. It  decreases the production of acid from the lining of the stomach.  This protects the stomach, oesophagus and duodenum from irritation and ulceration. They work by blocking an enzyme (hydrogen-potassium adenosine tri-phosphatase) of the gastric parietal cell - so called proton pump inhibitor. Side effects are rare but include headache, diarrhoea and  skin rashes. Your doctor should be aware if you have problems with your liver and the recommended dose should not be exceeded..

Further general information Your doctors and specialist nurses are in an ideal position to give you relevant information on your disease and treatment as they know your individual circumstances. Cancerbackup has a help line (0808 800 1234) and a prize winning video available in English, Italian, Urdu, Bengali, Gujarati & Hindi explaining Radiotherapy & Chemotherapy. has over 500 pages describing cancer, its management, practical tips and tool which patients, their carers and their doctors have found helpful during the cancer journey.

Lifestyle tips Aide gut health Micronutrient tests Protect nails
Amazing polyphenols