What are the directions for using acetic acid 2% (antifungal/antibacterial) ear solution for treating outer ear infections (otitis externa)?

Acetic Acid 2% Ear Solution Administration

For acetic acid 2% ear drops, instill 3-5 drops into the affected ear 3-4 times daily (3-4 drops in children) after thorough ear canal cleaning, continuing treatment for at least 7 days and up to 14 days maximum if symptoms persist. 1

Initial Preparation and Ear Canal Cleaning

• Before first application, all cerumen and debris must be carefully removed to allow the solution to contact infected surfaces directly. 1
• If the ear canal is obstructed by swelling or debris, your clinician should perform aural toilet (cleaning) or place a wick to enhance medication delivery. 2, 3

Wick Placement (When Needed)

• If your clinician places a cotton wick saturated with acetic acid solution, keep it in place for at least 24 hours and maintain moisture by adding 3-5 drops every 4-6 hours. 1
• After 24 hours, the wick may be removed, but continue instilling 5 drops (or 3-4 drops in children) 3-4 times daily thereafter. 1
• Do not remove the wick yourself unless instructed—if it falls out on its own, this indicates the inflammation is clearing. 2, 3

Proper Drop Administration Technique

• Have someone else administer the drops when possible, as only 40% of patients who self-medicate do so correctly during the first 3 days. 3
• Lie down with the affected ear facing upward. 2, 3
• Fill the ear canal completely with drops and remain in this position for 3-5 minutes—use a timer to ensure adequate penetration time. 2, 3
• Gently move the ear in a to-and-fro motion, or press the tragus (small cartilage in front of the ear) with an in/out movement to help distribute the medication. 2, 3
• After 3-5 minutes, get up and wipe off excess drops. 2

Treatment Duration and Monitoring

• Continue treatment for at least 7 days, even if symptoms improve sooner, to prevent relapse. 4, 5
• If symptoms persist beyond 7 days, continue drops until symptoms resolve, for a maximum total of 14 days. 4, 1
• Expect symptoms to last approximately 6-8 days after starting treatment with acetic acid alone. 5, 6
• If symptoms persist beyond 14 days, contact your doctor as this represents treatment failure requiring alternative management. 5

Precautions During Treatment

• Keep the ear dry throughout treatment—cover the ear canal with an earplug or petroleum jelly-coated cotton before showering or hair washing. 3, 7
• Avoid scratching, touching, or inserting anything (including cotton-tipped swabs) into the ear canal. 3, 7
• Do not clean the ear yourself, as the canal is tender and you could damage it or the eardrum. 2

Warning Signs

• If you taste the eardrops, this indicates a possible eardrum perforation—inform your doctor immediately. 2, 3
• Contact your doctor if drops become painful, you develop unexpected symptoms, or pain fails to improve within 48-72 hours. 3, 4

Important Clinical Context

Acetic acid 2% alone is less effective than antibiotic/steroid combination drops when treatment extends beyond one week. 5, 6 While acetic acid shows comparable efficacy at week 1, it demonstrates significantly lower cure rates at weeks 2 and 3 (OR 0.29 and 0.25 respectively), and patient symptoms last approximately 2 days longer compared to antibiotic/steroid combinations. 5 Studies show cure rates of only 38% at 7 days with acetic acid alone versus 68% at 14 days when corticosteroids are added. 6