Baytril has been the go to drug for longer then 10 years because it is affective. But yes there are strains resistant to it just like with anything but it still is the leading drug used for ri in reptiles because it works well. I always keep it on hand so i have it when needed. Havent had a snake die in 15 years from a ri. But im not saying do as i do. What i do works for me is all my point is.