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My dog has a soft lump after a vaccine shot. Is it normal or serious?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | neutered | 3 months and 27 days old

Pocholo was given a vaccine last December 26,2016. Just today, I noticed a small soft lump on his skin at the back where the injection was administered. It's like a cyst with water inside because it's very soft. Is Pocholo be okay and if I will apply a hot compress, will it be gone?

1 Answer

Most Helpful Answer

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Answered By Dr. Leigh, DVM

Veterinarian

Published on January 6th, 2017

That is a very common occurrence after vaccination. The vaccine can cause a localized reaction and it should resolve on its own within a month. If it persists, seems larger, or bothers him that have your vet take a look at it.

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