Background: A precise, user-friendly, sensitive, and verified spectrophotometric approach has been devised for the determination of erdosteine (ERD) in both pure and dose forms. This approach employed N-bromosuccinimide (NBS) as an eco-friendly oxidizing agent alongside three chosen dyes: amaranth (AM), methylene blue (MB), and indigocarmine (IC). The techniques utilize surplus quantities of NBS in acidic environments to oxidize erdosteine. The unreacted NBS is quantified chemically using fixed amounts of dyes AM, MB, and IC. Absorption was quantified at 520 nm, 663 nm, and 609 nm for AM, MB, and IC dyes, respectively. The analytical technique was executed and validated through a comprehensive examination and optimization of many elements that could potentially interfere with the reaction. Under optimum conditions, substantial linear correlations were identified, with correlation values between 0.9993 and 0.9996. These relationships were valid within concentration ranges of 1.0-16, 1.0-12, and 1.0-14 µg/ml, respectively. The LOD values obtained were 0.29, 0.28, and 0.30 μg/ml, while the LOQ values were established at 0.97, 0.93, and 1.0 μg/ml for the AM, MB, and IC procedures, respectively. The established methods were validated per ICH recommendations and effectively utilized for the analysis of erdosteine in dosage forms, demonstrating high accuracy and precision. The reliability of the approaches was confirmed through recovery studies utilizing the usual addition method. The statistical comparison of findings derived from the proposed methods against those from the published approach, utilizing Student's t-test and variance ratio F-test at a 95% confidence level, demonstrated strong concordance and indicated no significant disparity in accuracy and precision.