Objective: The aim of the study is to evaluate the effect of boric acid and dexamethasone-ciprofloxacin combination used in the treatment of acute diffuse external otitis on healing and on the external ear canal microbial flora.

Material and Method: Patients taking dexamethasone-ciprofloxacin combination were considered as group 1, and patients who received 2% boric acid were considered as group 2. During the first examination, on the 3rd and 7th days of treatment, patients were scored according to their examination findings and complaints. The groups were statistically evaluated between themselves and within according to the total recovery scores. In addition, the results of the patients who were cultured from the outer ear canal on the 7th day of treatment were interpreted according to the group they were in.

Results: In both groups, the patients progressed the recovery phase after the beginning of the treatment. While the average difference of total recovery score between the first and 7th day was 6.93±3.01 in group 1 which was 8.60±2.06 in group 2 (p =0.88). At the end of the third day compared to the baseline, the mean of the total recovery score difference of group 1 was 2.60 ± 2.44, while in group 2 this mean score was found to be 4.4 ± 1.80 (p =0.009). Although there was less reproduction in group 2, the most common identified organism was Pseudomonas aeruginosa in our study.

Conclusion: The use of boric acid alone in acute diffuse external otitis seems to be an effective treatment option.