The aim of this study was to formulate the thermoreversible gel containing riboflavin and dexamethasone to treat keratoconus. Gel was prepared by the cold method by mixing the poloxamer 407 as a thermosensitive polymer and HPMC as viscosity enhancing agent. The formulation was evaluated for pH, clarity, isotonicity, visual appearance. Also, gelation temperature, drug content, ex vivo permeation study, bioadhesive strength, hemolytic toxicity, rheological properties have also been evaluated. All results for this formulation were found to be in an acceptable range. Bioadhesive strength increased with HPMC concentration. The pH of the formulation was found to be 6.1 to 6.51. The gelation temperature was found to be in the range 30-38 • C. F5 formulation showed maximum drug release of 99.77% and 98.8% for riboflavin and dexamethasone, respectively, within 8 h. Hemolytic study revealed no change in the shape or surface of blood cells. In vitro keratoconus model was developed in mice using keratoconus and corneal fibroblast cells. The results revealed the that increased thickness of cell lines. The formulated gel played important role in the increasing thickness of cells. Further, the overall study demonstrates the safe and effective use of riboflavin and dexamethasone in the treatment of keratoconus.How to cite this article: Wo, N., Zhai, J.: Combinatorial therapeutic drug delivery of riboflavin and dexamethasone for the treatment of keratoconus affected corneas of mice: Ex vivo permeation and hemolytic toxicity.