What is swimmers ear and do the drops work?

What the evidence says

Swimmer's ear (otitis externa) is an infection or inflammation of the skin lining the ear canal. It happens when water gets trapped in the ear after swimming or bathing, softening the skin so bacteria (or sometimes fungus) can take hold and cause pain, itching, and sometimes discharge. For treating an active infection, ear drops do work.

A Cochrane review of randomized trials found topical treatments alone (without oral antibiotics) are effective for uncomplicated cases, and in most cases it doesn't matter much which topical drop is used. A Canadian children's health resource notes swimmer's ear is usually treated with prescription eardrops. Plain acetic acid (vinegar-based) drops worked about as well as antibiotic/steroid drops in the first week, but symptoms lasted a bit longer with acetic acid alone when treatment needed to continue longer, so many clinicians reserve it for milder cases or use it alongside antibiotics.

For preventing swimmer's ear, over-the-counter drying drops (used before and after swimming) are commonly recommended by Canadian and other health sources, and make physiological sense since they help dry the canal and lower its pH. However, the systematic review evidence found no direct randomized trials actually proving these prevention drops reduce infection risk, so this advice is based on reasoning and clinical experience rather than proven trial results. See a doctor if there's fever, spreading redness/swelling around the ear, or if symptoms don't improve within a week of using drops, since these can signal a more serious infection needing different treatment.