I bought it for my kittens because they are small and I didn't want to expose them to chemicals at such a young age. At first, let's say it did something, it killed a few, but that was only after one or two uses. After that, it didn't do anything, it barely managed to scratch a couple and left them almost alive, so I had to go outside to prevent them from jumping inside the house. Conclusion? Money wasted, if it doesn't have an effect on animals, let alone on humans, it is completely useless.