Pharynx

The pharynx is the top part of the airway which lies behind the mouth and nasal passages and runs down to the start of the oesophagus. The pharynx is part of both the respiratory (breathing) and digestive (swallowing) systems in the body. It is often mistaken for the larynx but it is located in a different part of the throat, above the larynx plus the oesophagus and trachea.

As a result of this, food, liquid and air pass through the pharynx although this is carefully controlled by the epiglottis. This flap of tissue folds down over the trachea and stops food from entering there, causing choking or aspiration (access to the lungs).

The pharynx has another equally important role, that of speech production and the ability to produce vocal sound (singing). The pharynx is comprised of three sections:

• Nasopharynx
• Oropharynx
• Laryngopharynx

Nasopharynx

The nasopharynx is located at the upper most point of the pharynx. This ‘nasal’ part of the pharynx – hence the name, runs from the base of the skull to the soft palate and tissues within the nasal passages.

Another aspect of this is the Eustachian tubes: these ‘auditory tubes’link the middle ear cavities to the pharynx –in this case they open out into the nasopharynx. This opening controls air pressure within the middle ear so that sound waves are able to pass through on their way to the brain.

Oropharynx The oropharynx is situated behind the oral cavity (mouth) and includes the uvula, tonsils, epiglottis and base of the tongue.

Laryngopharynx The laryngopharynx is the bottom part of the pharynx and runs from the epiglottis to the larynx and oesophagus. These structures are located beneath the oropharynx.

What is likely to go wrong with the pharynx?

The most likely condition to affect the pharynx is pharyngitis which is, in effect, a sore throat and is usually caused by a viral infection.

Pharyngitis is discussed in more detail in our throat infections section. Another problem is dysphagia or difficulty swallowing which is either a symptom of another condition or a disorder in its own right. There are many causes of dysphagia which are discussed along with the disease itself in our throat related problems section.