Amoxicillin is the first-line antibiotic for most ear infections in both children and adults. It’s effective against the bacteria that most commonly cause middle ear infections, it’s inexpensive, and it has relatively few side effects. But the specific antibiotic, dose, and duration depend on the type of ear infection, the patient’s age, allergy history, and whether the first round of treatment works.
Middle Ear Infections: Amoxicillin First
The most common ear infection, acute otitis media, affects the middle ear and typically follows a cold or upper respiratory infection. The three bacteria responsible for most cases are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Amoxicillin covers these well and remains the standard starting point.
The dose matters. In areas where antibiotic-resistant bacteria are common, a high-dose regimen (roughly double the standard dose) is recommended. Resistance is not rare: studies of children with ear infections have found that nearly 30% of pneumococcal bacteria cultured from middle ear fluid showed some level of penicillin resistance. The higher dose overcomes that resistance in many cases. In areas where resistance rates are low, the standard dose is often sufficient.
When Amoxicillin Doesn’t Work
If symptoms haven’t improved after 48 to 72 hours on amoxicillin, the typical next step is amoxicillin-clavulanate. This combines amoxicillin with a compound that blocks the defense mechanism some bacteria use to deactivate the antibiotic. It’s particularly useful against Haemophilus influenzae and Moraxella catarrhalis strains that resist plain amoxicillin. The FDA-recommended treatment course for this combination is 10 days for ear infections.
Alternatives for Penicillin Allergies
If you or your child has a mild or non-severe penicillin allergy, several alternatives work well. These include cefdinir, cefuroxime, and cefpodoxime, all taken by mouth, or ceftriaxone given by injection for up to three days. These belong to the cephalosporin class, which is related to penicillin but tolerated by most people with non-severe penicillin allergies.
For severe penicillin allergies, where the reaction involved hives, swelling, or difficulty breathing, cephalosporins may also pose a risk. In those cases, levofloxacin can be considered as an alternative.
Not Every Ear Infection Needs Antibiotics Right Away
Many ear infections, especially mild ones, resolve on their own. The CDC outlines specific criteria for a “watchful waiting” approach, where you monitor symptoms for two to three days before starting antibiotics. This applies to:
- Children 6 to 23 months old if only one ear is infected, symptoms have lasted less than two days, pain is mild, and temperature is below 102.2°F
- Children 2 years and older if one or both ears are infected and they meet those same symptom thresholds
The idea is to avoid unnecessary antibiotic use while keeping a prescription on standby. If symptoms worsen or don’t improve within two to three days, you fill the prescription and start treatment. This approach reduces antibiotic exposure without increasing the risk of complications.
How Long the Course Lasts
Treatment duration isn’t one-size-fits-all. Children under two years old, or anyone with severe symptoms, typically get a full 10-day course. Children two and older with mild to moderate symptoms can often be treated effectively with a five- to seven-day course. Shorter courses reduce side effects like diarrhea and rash while still clearing the infection.
Outer Ear Infections Use Different Antibiotics
If the infection is in the ear canal rather than behind the eardrum, it’s otitis externa, commonly called swimmer’s ear. This is a different condition caused by different bacteria, and it’s treated with antibiotic ear drops rather than oral antibiotics. The most common prescription is ciprofloxacin combined with a steroid to reduce swelling and pain. The antibiotic kills the bacteria while the steroid addresses inflammation.
When using these drops for swimmer’s ear, you lie on your side and gently pull the outer ear upward and backward to let the drops flow into the ear canal. For children who have ear tubes and develop a middle ear infection, the same drops can sometimes be used, but the technique is different: you press the small flap of cartilage in front of the ear opening in a pumping motion to push the drops through the tube.
Chronic Ear Infections Are a Different Problem
Ear infections that persist or keep recurring involve a different set of bacteria than acute infections. Chronic otitis media is more likely to harbor Pseudomonas aeruginosa, Staphylococcus aureus, and occasionally fungal organisms. These infections require different antibiotics and often need evaluation by a specialist, since the treatment approach and underlying causes differ significantly from a straightforward acute infection.