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Why is my new puppy sick with fleas, worms, vomiting, and a lump?

Updated On September 23rd, 2025

Pet's info: Dog | German Shepherd | Male | unneutered | 1 month and 12 days old | 25 lbs

My puppy has fleas and ticks. I found a long thin worm in his poop. I just found an inflamed-pus-leaking mass on his armpit. He also looks really sad (maybe lethargic). He has thrown up 3 times since i got him 1 &1/2 weeks ago. He has a vet appointment on Monday but can you please tell me what this could be?

1 Answer

Most Helpful Answer

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Answered By Andrea M. Brodie, DVM

Veterinarian

Published on July 7th, 2018

It sounds like your puppy is quite sick with worms and ectoparasites. This alone can make it sad, thin and ill, and can even kill it if not treated. Your vet will advise you on flea control (ask about it!) and will deworm your puppy. Apparently the breeder did not do a good job raising this puppy.

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