Swimmer’s ear is an infection in the outer ear canal, which runs from your eardrum to the outside of your head. It’s often brought on by water that remains in your ear after swimming, creating a moist environment that aids bacterial growth.
Putting fingers, cotton swabs or other objects in your ears also can lead to swimmer’s ear by damaging the thin layer of skin lining your ear canal.
Swimmer’s ear is also known as acute external otitis or otitis externa. The most common cause of this infection is bacteria invading the skin inside your ear canal. Usually you can treat swimmer’s ear with eardrops. Prompt treatment can help prevent complications and more-serious infections.
Swimmer’s ear symptoms are usually mild at first, but they may get worse if your infection isn’t treated or spreads. Doctors often classify swimmer’s ear according to mild, moderate and advanced stages of progression.
Mild signs and symptoms

• Itching in your ear canal
• Slight redness inside your ear
• Mild discomfort that’s made worse by pulling on your outer ear (pinna, or auricle) or pushing on the little “bump” (tragus) in front of your ear
• Some drainage of clear, odorless fluid
• Moderate progression

More intense itching

• Increasing pain
• More extensive redness in your ear
• Excessive fluid drainage
• Discharge of pus
• Feeling of fullness inside your ear and partial blockage of your ear canal by swelling, fluid and debris
• Decreased or muffled hearing

Advanced progression

• Severe pain that may radiate to your face, neck or side of your head
• Complete blockage of your ear canal
• Redness or swelling of your outer ear
• Swelling in the lymph nodes in your neck
• Fever