The uvula (pronounced /ˈjuːvjələ/) is the conic projection from the posterior edge of the middle of the soft palate, composed of connective tissue containing a number of racemose glands, and some muscular fibers (musculus uvulae). It is frequently confused with the epiglottis and the tonsils.
Function in voice
The uvula plays a key role in the articulation of the sound of the human voice to form the sounds of speech. Anita O'Day, a popular big band singer, had her uvula accidentally removed during a childhood surgery when only her tonsils were intended to be removed. This affected her voice by eliminating vibrato, she said, in an interview with Terry Gross of NPR's "Fresh Air" radio show, although the uvula is not responsible for vibrato (the vocal cords make this happen).
 Function in languages
The uvula functions in tandem with the back of the throat, the palate, and air coming up from the lungs to create a number of guttural and other sounds. Uvular consonants are not found in most dialects of English, though they are found in many Semitic, Caucasian, and Turkic languages, as well as several languages of Western Europe such as German and French. Certain African languages use the uvula to produce click consonants as well, though other than that, uvular consonants are fairly uncommon in Sub-Saharan Africa. In English (as well as many other languages), it closes the nasal passage to prevent air escaping through the nose when making nasal consonants.
 Universal emetic
Massaging the uvula causes the gag reflex to initiate and expel stomach contents, providing a universal alternative to emetic drugs such as ipecac. This is often an issue for people who plan to get uvula piercings.
 Velopharyngeal insufficiency
In a small number of people, the uvula does not close properly against the back of the throat, causing a condition known as velopharyngeal insufficiency or VPI. This causes "nasal" (or more properly "hyper-nasal") speech, where a lot of extra air comes down the nose, and the speaker is unable to say certain consonants, for example producing the sound /b/ like /m/.
 Snoring and sleep apnea
The uvula can also contribute to snoring or heavy breathing during sleep; having an elongated uvula can cause vibrations which lead to snoring. In some cases this can lead to sleep apnea, which may be treated by removal of the uvula or part of it if necessary, an operation known as uvulopalatopharyngoplasty (commonly referred to as UPPP, or U3P). However, this operation can also cause sleep apnea if scar tissue forms and the airspace in the velopharnyx is decreased. The success of UPPP as a treatment for sleep apnea is unknown, but some research has shown 40"60% effectiveness in reducing symptoms. Typically apnea subsides for the short term, but returns over the medium to long term, and sometimes is worse than it was before the UPPP.
 Nasal regurgitation
During swallowing, the soft palate and the uvula move superiorly to close off the nasopharynx, preventing food from entering the nasal cavity. When this process fails, the result is called nasal regurgitation. It is common in people with VPI, the myositides and neuromuscular disorders.
A child's swollen uvula with tonsils
An adult's swollen uvulaAt times, the mucous membrane around the uvula may swell, causing the uvula to expand 3"5 times its normal size. When the uvula touches the throat or tongue, it can cause sensations like gagging or choking, even though there is no foreign matter present. This can cause problems breathing, talking, and eating.
There are many theories about what causes the uvula to swell, including dehydration (e.g. from arid weather); excessive smoking or other inhaled irritants; snoring; allergic reaction; or a viral or bacterial infection. An aphthous ulcer which has formed on the uvula can also cause swelling and discomfort.
If the swelling is caused by dehydration, drinking fluids may improve the condition. If the cause is a bacterial infection, gargling salt water may help. However, it can also be a sign of other problems. Some people with a history of recurring uvulitis have to carry an EpiPen containing Adrenaline (Epinephrine) to inject themselves whenever the uvulitis begins. A swollen uvula is normally not life threatening and subsides in a short time, typically within a day.