Cat anthelmintics are still effective when dropped on the hair, but they will affect the effect of the anthelmintic, because the anthelmintic needs to penetrate the body through the skin. If it is dropped on the hair, it will only have a local effect, so it is best to It is best to drop it on the cat's skin and on the back of the neck to prevent the cat from accidentally licking it and causing poisoning. You can also wear an Elizabethan ring on the cat.
Tips:
Cats need to be dewormed externally once a month, which can effectively prevent parasites.