I've used it only once for snake mites (on a blood python, incidentally), and use it a lot around the farm -- insect control on livestock quarters (and directly on livestock when it is really needed -- fly strike is nasty), treating clothing for ticks, spraying the siding of the house against wasps and carpenter bees. Since I use a fair amount of it, I've done some research into how to use it safely, and making sure it is dry on a surface is really important, since then it stays there and works its magic. Based on what I read in journal articles, it is very safe and effective for snake use when used judiciously.