Objective: To compare transdermal permeability properties in vitro of Calamine lotion with different mesh size. Method: Modified Franz diffusion cell was used

excised rat skin was applied as permeability barriers. Permeability quality of ZnO was determined by titration

transdermal rate constant and lag time were computed. Result: Transdermal permeability in vitro of ZnO in vitro was in accordance with zero-order release kinetics.Compared with other size

transdermal permeability in vitro of Calamine with 1 000 mesh size was relatively good. Conclusion: With size of Calamine decreasing

accumulative penetration amount trended to increase

and contributed to transdermal permeability.