Frequent swimmers sometimes notice a buildup of fluid in the middle ear after swimming and wrongly blame pool or sea water as the source. In fact, the middle ear is protected from exterior fluids by the eardrum, although the pressure caused by swimming underwater can sometimes make middle ear pressure more noticeable. The sooner you get treated for middle ear fluid, the sooner you will be able to go back to enjoying water sports and activities that involve swimming.
Otitis Media
The middle ear area, just behind the eardrum, can become filled with fluid and inflamed, causing pain and dampening hearing. This type of infection, called otitis media, can cause the eardrum to rupture if the pressure builds up too high behind it. The causes of otitis media vary, but they all involve the buildup of fluids from inside the ear, not trapped external fluids such as water from swimming or bathing. The tube that makes up the middle ear stretches from the back of the eardrum down to the back of the throat and does not connect with the outer ear.
Swimming
Swimming cannot cause otitis media, since the water from swimming can't actually get into the middle ear past the eardrum. However, swimming or diving underwater can put pressure on the eardrum that makes an already-existing middle ear infection worse. If the eardrum has ruptured, you should avoid swimming or diving until it has healed.
Persistent Middle Ear Fluid
If the fluid trapped in the middle ear does not dissipate on its own or if it recurs frequently, it can cause a chronic middle ear infection. Over time the fluid can thicken and cause cysts or changes to the middle ear. A persistent infection often has milder symptoms than an acute infection, even while it is causing more permanent damage. This is why it's important to treat any fluid in the middle ear, even when the buildup seems mild.
Treatment
An inner ear infection that causes a buildup of fluid can be treated with prescription antibiotics. Your doctor might also recommend ibuprofen or acetaminophen to ease pain and inflammation. You can also try applying a warm, moist cloth over the outside of the affected ear to ease pain and discomfort. If the problem becomes persistent, you might need to have ear surgery to drain the interior of the ear and repair the eardrum or middle ear bones. After surgery, you might need to avoid underwater swimming until the ear has healed. If the doctor has placed ear tubes into your eardrum to drain your middle ear, you will need to protect the middle ear when swimming by using earplugs.
