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Why are my dog's fleas smaller, slower, and falling off after meds?

Updated On September 23rd, 2025

Pet's info: Dog | Yorkipoo | Male | neutered | 4 years and 4 months old | 13 lbs

My dog has fleas. This is the second time my dog has them. The first time they were jumping like crazy and big. This time they are not jumping and are falling on the ground and moving slow. I can easily catch them and they are smaller then the first time. Why is that? Are they dying because i gave my dog oral flea meds? I definitely see them in my bed.

1 Answer

Most Helpful Answer

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Answered By Destini R. Holloway, DVM

Veterinarian

Published on October 2nd, 2019

I can understand your concern here. It sounds like the fleas are dying off, which is why they appear smaller and are falling off Shadow. It can take several treatments (2-3 months) to break that flea cycle and get rid of fleas completely when you pet is infested with them. There are some ways to speed up the process though, which includes giving Shadow a good Dawn Dish detergent bath, followed by a regular dog bath to help keep his skin moisturized. Then I would recommend treating your home with a flea fogger purchased from either Lowe's or Home Depot. These suggestions should help you get a handle on the fleas and flea eggs a bit better and gain control of your flea problem Thanks for visiting Petco Pet Education Center, formerly Petcoach and good luck with Shadow and his fleas. Take care!

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