OBJECTIVE: This study aimed to compare the cerumenolytic efficacy of 2.5 % sodium bicarbonate prepared in-house with that of commercially available 0.5 % sodium docusate, utilizing cerumen weight gain and disintegration degree as metrics. METHODS: Cerumen samples were collected from patients at an otorhinolaryngology outpatient clinic at a tertiary care hospital. This study evaluated the differences in cerumen weight and degree of disintegration in vitro before and after treatment with cerumenolytic agents at 15 and 30 min and at 1, 2, 4, 6, and 24 h. The agents tested were 2.5 % sodium bicarbonate and 0.5 % sodium docusate. Each experiment was conducted at least five times. We hypothesized that greater weight gain and higher disintegration scores indicate better cerumenolytic efficacy. RESULTS: Both cerumenolytic agents caused significant increases in wet and dry cerumen weights at all time points (P <
0.001). After 24 h, the cerumen weight increased approximately sevenfold from the initial weight. Notably, the weight increased by 50 % of the 24-hour value within the first hour. A comparison of the average weight gain between the 2.5 % sodium bicarbonate and 0.5 % sodium docusate groups revealed no significant differences at any time point (P = 0.406). Similarly, disintegration scores obtained via the 96-well plate method were not significantly different (P = 0.749). CONCLUSIONS: In terms of cerumen weight gain and degree of disintegration, the cerumenolytic efficacy of 2.5 % sodium bicarbonate is not inferior to that of 0.5 % sodium docusate. A 1-hour application of a cerumenolytic agent is effective for cerumen removal in outpatient settings.