Purpose <p>The fixed-dose combination of Norfloxacin and Tinidazole Tablets is extensively utilized for the treatment of diarrhea and amoebic dysentery in the southern region of the Asian subcontinent, particularly in India. However, the dissolution test procedure for the quality assessment of the finished product has not been documented in any reputable pharmacopoeia, such as USP, BP, Ph. Int.IP, Ph. Eur., and JP, nor has it been reported in any journal. Therefore, the objective of this study was to develop a robust dissolution method for assessing the in vitro release of Norfloxacin and Tinidazole in a fixed-dose combination.</p> Method <p>The dissolution profiles of Norfloxacin and Tinidazole Tablets were determined using four different dissolution media (Water, 0.1 N Hydrochloric Acid, Acetate Buffer pH 4.5, and Phosphate Buffer pH 6.8), two apparatuses (Basket and Paddle), and three different agitation speeds (50, 75, and 100 rpm).</p> Results <p>The method employing a paddle apparatus at 50 rpm in 900 mL of 0.1 N Hydrochloric Acid demonstrated superior hyper-discriminating capability with a Q30 value ≥ 90%. The selected method was successfully validated in accordance with the ICH Q2 (R2) guidelines for AMV, meeting all parameters of analytical method validation.&#xa0;</p> Conclusion <p>An in vitro release assessment method for the determination of Norfloxacin and Tinidazole was successfully developed and validated according to the revised guidelines for analytical method validation (ICH Q2 (R2)). Consequently, the developed method demonstrates robustness and ruggedness and can be employed for the quality assessment of Norfloxacin and Tinidazole Tablets prior to market release.</p> Graphical abstract <p></p>