Can cat deworming kill fleas?

External deworming of cats can kill fleas. The mortality rate of fleas is more than 90%, but it takes 1 to 2 days to kill fleas. Cats need to be dewormed externally once a month to effectively prevent fleas or other parasites.
Tips:
Try not to take your cat out, especially around summer, to prevent your cat from being bitten by mosquitoes; your home should also be cleaned and disinfected regularly.