The medical term for any difficulty or discomfort when swallowing is dysphagia. A normal swallow takes place in four stages, and involves 25 different muscles and five different nerves. And if you understand a normal swallow, it will help you understand why problems may develop.
The sight, smell, or taste of food and drink triggers the production of saliva, so that when you put food in your mouth (usually voluntarily) there is extra fluid to make the process of chewing easier.
When the food is chewed enough to make a soft bolus, your tongue flips it towards the back of the mouth to the top of the tube, which leads down to your stomach. This part of your throat is called the pharynx. This part of swallowing is also voluntary.
Once the bolus of food reaches your pharynx, the swallowing process becomes automatic. Your voice box (the larynx) closes to prevent any food or liquid getting into the upper airways and lungs, making the food bolus ready to pass down your throat (known as the oesophagus).
Your oesophagus, which is a tube with muscular walls that contract automatically, then propels the food down to your stomach.
If you find it difficult to swallow, the problem can occur at any one or more of these four stages. Difficulties at different stages cause different problems and symptoms.