The Anatomy of the Pharynx

Tube used by both the respiratory and digestive systems

Table of Contents
View All
Table of Contents

The pharynx is most commonly referred to as the throat. It's a muscular tube that starts at the base of the skull behind the nasal cavity, and extends down to the larynx (voice box) and esophagus, the tube that leads to the stomach.

Its primary functions play a role in both the digestive and respiratory systems. The pharynx takes in air from the nasal passages as well as food and drink from the mouth. The pharynx is also what helps you speak, as muscles in the throat vibrate to help produce sound.

This article explains the structure and function of the pharynx. It also discusses medical conditions that can affect the pharynx, as well as some of the tests and treatment options used for them.

doctor looking at man's throat and pharynx
 Martin Barraud/Getty Images

Anatomy

The pharynx consists of three major sections:

  • The nasopharynx is the top part of the throat.
  • The oropharynx makes up the middle part behind your mouth.
  • The laryngopharynx is the lowest part. It is found behind the voice box.

Structure

The pharynx as a whole is about 13 centimeters (cm) in length. While the tube is largely made up of muscle, some areas consist of soft tissue.

For example, the nasopharynx is made up of respiratory epithelium. This is a protective mucous membrane that coats the airways and respiratory tract.

The nasopharynx is also where part of your tonsils are located; the oropharynx contains the rest, as well as the back part of your tongue and a muscle that helps you to swallow.

The laryngopharynx contains two groups of pharyngeal constrictor muscles. Together, these muscles help push food down into the esophagus for digestion.

Apart from these more circular constrictor muscles, the pharynx also has several longer muscles to shorten and expand its space and push the larynx up when swallowing.

If swallowing seems like it’s a complicated function, that’s because it is. In fact, it takes approximately 25 pairs of muscles in the mouth, pharynx, larynx, and esophagus to do this.

The vagus nerve is another key part of the anatomy of the pharynx. It runs through the face, neck, and abdomen and transmits messages to and from the brain. Among other things, the vagus nerve helps control the motor and sensory functions of the pharynx, including swallowing.

Anatomical Variations

For the pharynx to work properly, its structure needs to be precise. Changes from the norm are called anatomical variants, and they can have health impacts.

For example, some people have changes in the lateral (side) wall of the oropharynx. Researchers have noted a link between these changes and sleep apnea, a condition that causes people to stop breathing on and off while sleeping.

Some changes may be considered "normal variants." The thyrohyoid membrane, for example, can become weak in older people. It also shows changes in younger people who engage in activities that involve pressure in the pharynx, like playing the trumpet. This can change the lateral pharynx wall too.

Function

Because of its location, the pharynx helps the respiratory system by allowing air to pass through the trachea, or windpipe, to your lungs.

For digestion, the muscles surrounding the pharynx work together to send food and drink into the esophagus. The circular muscles push food and drink toward the intestines, while the longer muscles widen and lift the pharynx, making it possible to swallow.

The pharynx also plays a role in speech. It is an enclosed space that can change shape thanks to its muscles, so air is able to travel through the pharynx to the voice box. As vocal cords work to make sound and the larynx opens up, the pharynx is able to amplify that sound.

Associated Conditions

Medical conditions that affect the pharynx range from the mild to severe. Some may go away on their own, while others require treatment. They also will be treated differently depending on the cause.

Among the conditions that may affect the pharynx are:

A number of remedies may be used to treat some of these common ailments and help to heal the pharynx. For example, over-the-counter sore throat remedies, or simply gargling warm salt water, may help relieve discomfort from a simple sore throat from a virus or cold.

Other cases will need to be treated on the basis of the specific diagnosis. If the cause is strep throat, for instance, antibiotics are needed to treat the bacterial infection.

If you have throat irritation due to gastroesophageal reflux disease (GERD), you will likely need medication to reduce the acid that's coming up and affecting the pharynx.

If you have a persistent sore throat that doesn’t go away after a few days to a week, it’s a good idea to make an appointment with a healthcare provider.

Tests

Your healthcare provider may order some tests to help determine the cause of your pharynx pain. These tests may include a laryngoscopy, which lets your healthcare provider look directly at the larynx and pharynx using a small device that has a scope on it.

If you have a chronic cough or sore throat, any voice changes, or difficulty breathing, this test may be the next step in determining the cause behind your symptoms.

Other tests may be needed, although they aren’t necessarily to evaluate the pharynx. They include:

Summary

The pharynx, or throat, plays a key role in serving both your respiratory and digestive systems. Its structures allow air to pass through your windpipe and on to your lungs, while also working to ensure food and drink pass into the esophagus and stomach. It also helps you to speak.

Many of the health conditions that affect the pharynx are common. They include the common cold, the flu, and strep throat. On the other hand, serious conditions such as throat cancer also may affect the pharynx.

Frequently Asked Questions

  • Can people develop cancer of the pharynx?

    Yes. Cancer of the pharynx is usually described by the part of the structure that's affected, such as nasopharyngeal or oropharyngeal cancer. About 90% of pharyngeal cancers are squamous cell carcinomas, and they tend to affect males more than females.

  • Is cancer of the pharynx connected to HPV?

    Yes, in some cases. The human papillomavirus (HPV), long associated with cervical cancer, is now linked to more oral cancers in the United States. HPV is strongly associated with cancer of the tonsils, although it can be found in almost any part of the mouth or throat. 

  • Does the pharynx play a role in difficulty when swallowing?

    The pharynx can play a role in dysphagia, or difficulty swallowing. There are three phases of swallowing, and trouble during the pharyngeal phase can lead to aspiration pneumonia and other complications if any of the mechanisms that keep food out of the lungs fail.

Was this page helpful?
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Bičanić I. The anatomy of orofacial innervationACC. 2019 Jun;58(Suppl 1):35-42. doi: 10.20471/acc.2019.58.s1.05

  2. Von Arx T, Lozanoff S, Bornstein MM. Extraoral anatomy in CBCT – a literature review. Part 4: Pharyngocervical region. Swiss Dent J. 2020;130(10):768-784.

  3. Schwertner RW, Garand KL, Pearson WG. A novel imaging analysis method for capturing pharyngeal constriction during swallowingJ Imaging Sci. 2016;1(1)

  4. Takeishi R, Magara J, Watanabe M, Tsujimura T, Hiyashi H, Hori K, et al. Effects of pharyngeal electrical stimulation on swallowing performance. Weng X, ed. PLoS ONE. 2018;13(1):e0190608. doi: 10.1371/journal.pone.0190608

  5. Lugo-Saldaña R, Saldívar-Ponce K, González-Sáez I, Hernández-Sirit D, Mireles-García P. Selecting different approaches for palate and pharynx surgery: palatopharyngeal arch staging systemInternational Journal of Head and Neck Surgery. 2019;10(4):92-97. doi: 10.5005/jp-journals-10001-1383

  6. Tao TY, Menias CO, Herman TE, McAlister WH, Balfe DM. Easier to swallow: pictorial review of structural findings of the pharynx at barium pharyngographyRadioGraphics. 2013;33(7):e189-e208. doi: 10.1148/rg.337125153

  7. Al-Tamimi J. Revisiting acoustic correlates of pharyngealization in Jordanian and Moroccan Arabic: Implications for formal representationsLaboratory Phonology: Journal of the Association for Laboratory Phonology. 2017;8(1):28. doi: 10.5334/labphon.19

  8. University of Michigan Medicine. Sore throat and other throat problems.

  9. Collins SR. Direct and indirect laryngoscopy: equipment and techniquesRespiratory Care. 2014;59(6):850-864. doi: 10.4187/respcare.03033

  10. Boston Medical Center. Voice and swallowing diagnostic tests.

  11. Chowdary SD, Sekhar PC, Kattapagari KK, Mani Deepthi CH, Neelima D, Reddy BVR. A study to assess expression of human papillomavirus types 16 and 18 in oral squamous cell carcinoma using polymerase chain reactionJ Oral Maxillofac Pathol. 2018;22(3):347-352. doi:10.4103/jomfp.JOMFP_139_17

  12. Centers for Disease Control and Prevention. HPV and cancer-statistics.