Effectiveness of 3% Boric Acid in 70% Alcohol Versus 1% Clotrimazole Solution in Otomycosis Patients

Effectiveness of 3% Boric Acid in 70% Alcohol Versus 1% Clotrimazole Solution in Otomycosis Patients: a Randomized Controlled Trial

Otomycosis is a superficial fungal infection of the external ear canal. Patients should be treated with cleaning fungal debris combined with topical antifungal agent. There is wide range of topical antifungal agents. However, there is still no consensus of the most effective topical antifungal agents in treatment otomycosis is still lacking.

According to Thai National List of essential medicines for topical antifugal agents are:

• acetic acid (2% in aqueous and 2% in 70% isopropyl alcohol)
• boric acid (3% in isopropyl alcohol)
• gentian violet
• clotrimazole ear drop. But from literature review, there is no comparative study between boric acid and clotrimazole solution before.

Objective is to compare the clinical effectiveness and adverse events of 1% clotrimazole solution versus 3% boric acid in 70% alcohol for the treatment of otomycosis.

The hypothesis has been formulated by H0 and Ha. H0 = 1% clotrimazole solution has clinical effectiveness not different from 3% boric acid in 70% alcohol for the treatment of otomycosis.

Ha = 1% clotrimazole solution has more clinical effectiveness than 3% boric acid in 70% alcohol for the treatment of otomycosis.

Inclusion criteria:

• Symptomatic otomycosis, age more than 7 year.
• Microscopic finding revealed fungus
• KOH smear positive for fungus

Exclusion criteria:

• Pregnancy
• Tympanic membrane perforation and post mastoid surgery
• Co-infection of ear e.g. severe otitis externa,severe myringitis which are needed other medication.
• Previous using topical antibiotic / steroid within 2weeks.
• During usage of systemic antifungal drug
• Allergic to 3% boric acid in 70% alcohol or 1% clotrimazole solution. PICO model: P= otomycosis patient I= 1%clotrimazole ear drop C= 3% boric acid O= result of treatment as cure

Inclusion Criteria:

• Symptomatic otomycosis, age more than 7 year.
• Microscopic finding revealed fungus
• KOH smear positive for fungus

Exclusion Criteria:

• Pregnancy
• Tympanic membrane perforation and post mastoid surgery
• Co-infection of ear e.g. severe otitis externa, severe myringitis which are needed other medications
• Previous using topical antibiotic / steroid within 2weeks.
• During usage of systemic antifungal drug
• Allergic to 3% boric acid in70% alcohol or 1% clotrimazole solution.
• Those who can not come to follow up after one week of the treatment