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Why does my puppy have a soft lump after vaccination? What to do?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | 6 months and 9 days old | 2 lbs

My 7month old puppy has a massive lump on his back it is a week after his vaccination for his skin disease. The disease is almost gone but then there's a soft lump like liquid on his back. The one who did the injection was the assistant and not the city vet. I am so worried any home treatment? Sorry the lump cant be seen I dont wanna wake them

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1 Answer

Most Helpful Answer

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Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS

Veterinarian

Published on March 3rd, 2019

The lump is likely to be caused by a tissue reaction due to the injection. If that is the case the lump will resolve, and will not have any consequence. If it persists more than two weeks or if it gets bigger a check up would be needed (as it could be infected). Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

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