Otitis externa: Infection of the skin covering the outer ear canal that leads in to the ear drum, usually due to bacteria such as streptococcus, staphylococcus, or pseudomonas. Swimmer's ear is usually caused by excessive water exposure. Infection with a fungus may also occur. When water pools in the ear canal (frequently trapped by wax), the skin will become soggy and serve as an inviting culture media for bacteria.
The first sign of otitis externa is that the ear feels full and may itch. Next the ear canal swells, ear drainage follows, and the ear is very painful, especially with movement of the outside portion of the ear. The ear canal can swell shut and the side of the face become swollen. The glands of the neck may enlarge, and it can become more difficult to open the jaw.
Moisture and irritation will prolong the course of otitis externa. For this reason, the ear should be kept dry. While showering or swimming, use an ear plug (one that is designed to keep water out), or use cotton with Vaseline on the outside. Scratching the inside of the ear or using Q-tips should be avoided. A hearing aid should be left out as much as possible until swelling and discharge stops. The most common treatment consists of antibiotic ear drops with or without an oral antibiotic. Antifungal drops may also be necessary for a fungal infection. A "wick" may need to be placed in the ear canal to stent it open and serve as a conduit for the ear drops. Suctioning the ear canal also helps.