Achalasia

The food that remains in the oesophagus can undergo fermentation and come back up into the mouth, resulting in a bitter taste. This is often mistaken for gastroesophageal reflux disease (GERD) but unlike GERD, the undigested food comes from the oesophagus and not from the stomach. The main symptoms are:

1. Dysphagia (difficulty in swallowing) of both liquids and solids
2. Regurgitation of undigested food
3. Chest pain/discomfort
4. Heartburn
5. Loss of weight