Acid reflux or indigestion. We all get it. Maybe we've eaten too much or too late in the evening. Maybe we've drunk too much alcohol at that party the night before. We could have bent down to do a bit of weeding too soon after a meal and oops, that pain in the middle of the chest can be quite severe.

What is acid reflux though?

It is the liquid in the stomach regurgitating into the oesophagus (gullet). Much of this liquid is acid produced in the stomach which is harmful to the walls of the oesophagus. Reflux happens to most people but because we spend much of our time upright, gravity ensures that the liquid returns to the stomach unnoticed. In addition, we swallow frequently which again returns regurgitated liquid to the stomach and saliva contains bicarbonate which helps to neutralise the acid in the stomach liquid.

It doesn't do to ignore repeated instances of painful indigestion though, as it could be symptomatic of something much more serious. That refluxing acid can cause lasting damage to the lining of the oesophagus, which, if left untreated, can lead to other conditions.

A friend relates that when she was a child, her father was always chewing on Rennies, a well known antacid in the UK. He used to say that a good belch would cure the indigestion. It later turned out that he had a stomach ulcer. Despite that, when my friend, in turn, started suffering from frequent indigestion, she too chewed on the Rennies and went about her business.

Eventually, she realised that the extent of the indigestion couldn't be normal so she consulted her doctor who referred her to a specialist for an endoscopy.

An endoscopy is a procedure whereby an endoscope, a thin, lighted tube, is inserted down the throat. The endoscope transmits images of the oesophagus, stomach, and duodenum, enabling the specialist to identify problem areas and, if necessary, obtain biopsies. The endoscope is usually inserted while the patient is under sedation thus avoiding the gagging reflex.

To return to my friend, a hiatus hernia was diagnosed. A hiatus hernia occurs when the upper part of the stomach pushes through the opening in the diaphragm where the oesophagus connects with the stomach, allowing the acid from the stomach to reflux. Fortunately, this was a small hiatus hernia, which could be easily treated with a course of medication.

A couple of years went by with only minor instances of indigestion, then my friend started to experience occasional bouts of very severe heartburn and sickness which she treated with the usual array of antacid preparations. Suddenly, one day she woke up with a severe pain in her lower stomach which didn't respond to the usual remedies and in any event, didn't resemble any of the normal symptoms of acid reflux.

A visit to the doctor and my friend found herself hospitalised for tests which revealed that the original small hiatus hernia was larger and bleeding and had lead to gastritis (inflammation of the stomach lining) and duodenitis (inflammation of the duodenum), both caused by an infection with the Helicobacter pylori bacteria. This bacteria is extremely common, thought to infect 70% of the world's population, although most people do not display any symptoms of the infection.

The moral of this story is "Don't ignore persistent acid reflux, it may be much more that just indigestion".

Watch out for my next article on the treatment of acid reflux.