This flea medicine works well enough for the fleas in my area. Luckily, they are not the kind that are resistant to this sort of medicine. The unfortunate thing is the packaging. It’s really distressing to my animals to put this on them in the first place. They don’t like it, so I have to sneak up on them to apply it. It really is disheartening after all of that to squeeze the packaging and absolutely nothing comes out. So I’ve traumatized my cats for absolutely nothing, and that makes it harder to get near them and try again. The packaging really stinks, and it’s why I’m going to cancel my subscription. I am so disappointed. I was thrilled to find a very affordable solution in these difficult times, but it’s only worth it if you could actually get the medicine on your pets.