Acid reflux refers to the backflow of acid and digestive enzymes from the stomach into the food pipe ​(oesophagus), throat (pharynx) and voice box (larynx).

What are the symptoms of acid reflux?

The more commonly experienced symptoms are:

  • Heartburn (sharp central chest pain associated with an episode of acidic stomach content rising up the oesophagus or food pipe)
  • Sour brash (a taste of acidic regurgitated food or liquid in the mouth)

In addition, some patients may have symptoms affecting their throat and voice box (laryngo-pharyngeal reflux), including:

  • Sensation of a lump or something being stuck in the throat (globus sensation)
  • Throat clearing
  • Hoarseness
  • Chronic cough

Ten per cent of people show daily symptoms of gastro-oesophageal reflux, and 50 per cent of people experience symptoms at least once a month.

However, if symptoms occur frequently or persistently, you should be evaluated for gastro-oesophageal reflux disease.

What causes reflux disease?

The lower oesophageal sphincter is a muscular band separating the oesophagus (food pipe) from the stomach. It normally tightens to prevent the backflow of acid and digestive enzymes. However, this protective mechanism is lost when:

  • The sphincter muscle loses its pressure or tightness. This can be caused by:
    • Smoking
    • Alcohol
    • Caffeine
    • Chocolate
    • Certain medications such as calcium channel blockers, anticholinergic agents and nitrates
    • Anatomical problems with the sphincter, such as hiatus hernia
  • The pressure inside the stomach is increased and overcomes that of the sphincter. This may occur if the person is obese or is:
    • Overeating
    • Having carbonated drinks
    • Exercising on a full stomach

While the lining of the stomach is well-adapted to withstand acid and digestive enzymes, the lining of the oesophagus, throat and voice box is not. The digestive enzymes and acid can cause injury to these sensitive tissues, leading to swelling, pain or discomfort and interfering with the normal clearance of mucus from the voice box and throat. This can trigger protective reflexes, giving rise to a chronic cough. In the long term, if left untreated, acid reflux can cause permanent damage to the lining of the voice box and food pipe.

Read on to learn how acid reflux is diagnosed and treated​.​

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