Otitis Externa: Swimmer’s Ear Causes and Drops That Actually Work

Swimmer’s ear isn’t just a nuisance-it’s a painful, sometimes debilitating infection that can turn a fun day at the pool into days of discomfort. If you’ve ever felt that sharp, throbbing pain when you tug on your earlobe, or noticed a feeling of fullness and muffled hearing after swimming, you’re not alone. About 1 in 10 Americans gets otitis externa every year, according to CDC estimates from 2022. It’s not caused by water trapped in the ear alone-it’s what happens after the water gets in.

Why Your Ear Gets Infected After Swimming

The ear canal is designed to protect itself. Normally, it’s lined with a thin layer of earwax (cerumen) that keeps moisture out and maintains a slightly acidic pH between 5.0 and 5.7. This acidity is like a natural antibiotic-it stops bacteria and fungi from growing. But when you swim frequently, especially in chlorinated pools or warm, stagnant water, that protective barrier breaks down. Water softens the skin, and repeated exposure creates tiny cracks. Suddenly, bacteria that normally live harmlessly on your skin get a free pass inside.

The two most common culprits are Pseudomonas aeruginosa and Staphylococcus aureus. Together, they cause more than half of all cases. Fungi like Aspergillus show up in about 10% of cases, especially in humid climates or after prolonged water exposure. People with diabetes, eczema, or those who use cotton swabs (even gently) are at higher risk. Why? Because cotton swabs scrape off wax, scratch the skin, and push debris deeper-creating the perfect breeding ground.

How Bad Can It Get?

Not all cases are the same. Most are mild: itching, slight redness, and discomfort when you move your jaw or pull your ear. That’s about 45% of cases. But moderate cases-35% of them-bring swelling that starts to block the ear canal. Hearing gets muffled. Pain becomes constant, even when you’re not touching your ear. Then there’s the severe form: 20% of cases. The canal swells shut. Lymph nodes under the jaw swell. Fever spikes above 101°F. This isn’t just painful-it’s dangerous. Without treatment, it can progress to malignant otitis externa, a rare but serious infection that spreads to the skull bone, especially in older adults or those with weakened immune systems.

What Ear Drops Actually Work?

The right treatment depends on what’s causing the infection-and how bad it is. For mild cases, over-the-counter drops like Swim-Ear (2% acetic acid with hydrocortisone) work well. They restore the ear’s natural acidity and reduce swelling. Studies show an 85% success rate for mild infections when used correctly. And here’s the bonus: using them after swimming can cut your risk of getting it again by 65%. They’re cheap-around $15 a bottle-and widely available.

But if your ear is swollen, painful, or you’ve had symptoms for more than a couple of days, you need something stronger. That’s where prescription drops come in. The gold standard is Ciprodex (ciprofloxacin and dexamethasone). It’s a combo of an antibiotic that kills bacteria and a steroid that reduces swelling. Clinical trials show it clears up moderate to severe cases in 92% of people within a week. It’s not cheap-$147.50 without insurance-but it’s often covered by plans. Generic ofloxacin drops work too, at about $45, and are nearly as effective.

Don’t use old-school drops like neomycin-polymyxin. They’re less effective (80-85% cure rate), and they carry a risk of permanent hearing damage if your eardrum is perforated-even if you don’t know it is. The FDA warns about this. Also, avoid using drops meant for fungal infections (like clotrimazole) unless you’ve been diagnosed with a fungal ear infection. Using the wrong drop delays real treatment. One study found that 15% of people who self-treated with OTC drops ended up with a fungal infection because they used antibacterial drops on a fungal problem.

How to Use Ear Drops Right (Most People Get It Wrong)

You can have the best drops in the world, but if you use them wrong, they won’t work. A 2021 study found that 40% of people reduce their treatment’s effectiveness just by how they apply it. Here’s how to do it right:

1. Wash your hands.
2. Warm the bottle in your hands for 1-2 minutes. Cold drops can make you dizzy.
3. Lie on your side with the infected ear facing up.
4. Pull your earlobe gently up and back to straighten the canal.
5. Instill the exact number of drops prescribed.
6. Stay still for 5 minutes. This lets the medicine reach deep into the canal.
7. Then, sit up and let any extra drip out.
8. Do not stick anything-cotton swabs, fingers, or Q-tips-into your ear.

Skipping the 5-minute wait cuts effectiveness by nearly half. And never use cotton swabs to dry your ear after. Just tilt your head and let it drain. If your ear is swollen shut, you’ll need an ear wick-a tiny sponge-like device your doctor inserts to help drops reach the infection. It’s uncomfortable, but it’s necessary.

What Not to Do

Don’t use home remedies like vinegar and alcohol mixes unless you’re sure you have a mild case and no eardrum damage. They’re not regulated, and the wrong mix can burn your skin. Don’t take oral antibiotics unless your doctor says so. Studies show they add almost nothing to topical treatment but increase side effects like stomach upset and yeast infections. And don’t ignore symptoms that get worse. If you develop fever, swelling in your neck, or pain that spreads to your face, see a doctor immediately. That’s not swimmer’s ear anymore-it’s something more serious.

Who’s Most at Risk?

Kids between 7 and 12 are the most common group affected-mostly because they swim often and don’t always dry their ears well. Adults 45 to 64 are next, especially those with diabetes or arthritis that makes it hard to reach their ears. Men are slightly more likely to get it than women, likely because they’re more likely to swim in public pools and less likely to use preventive drops. If you have eczema or psoriasis on your scalp or ears, your skin barrier is already compromised. That makes you more vulnerable.

Prevention Is Easier Than Treatment

The best treatment is avoiding the infection in the first place. After swimming or showering:

• Tilt your head to drain water.
• Use a hair dryer on low heat, held at least a foot away, to gently dry the ear.
• Use a few drops of over-the-counter acetic acid solution (like Swim-Ear) after swimming-especially if you’re prone to infections.
• Avoid cotton swabs, bobby pins, or anything that scratches the ear canal.
• If you wear hearing aids or earbuds daily, clean them regularly and give your ears a break.

There’s new research coming. Stanford is testing treatments that use the ear’s own microbiome to fight infection. But for now, the proven methods are simple: keep the ear dry, use the right drops, and don’t mess with it.

When to See a Doctor

You don’t need to run to the clinic for mild itching. But if you have:

• Pain that doesn’t improve after 2 days of OTC drops
• Fever or swollen lymph nodes
• Drainage that’s yellow, green, or bloody
• Difficulty hearing or dizziness
• Diabetes or a weakened immune system

Then see a doctor. They’ll use an otoscope to look inside, and if needed, take a sample to test for bacteria or fungus. They can also clean the ear canal properly-a step most people skip at home. Debridement (cleaning) alone can improve drop effectiveness by 30-40%.