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Why is my dog's lip swollen and red on one side all of a sudden?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed Medium (23 - 60lb) | Male | neutered | 1 year and 9 months old | 56 lbs

My dogs lips on one side are swollen and red this morning. Thoughts of what this could be?

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1 Answer

Most Helpful Answer

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Answered By Dr. Strydom, DVM

Veterinarian

Published on March 26th, 2020

It could be a contact allergy where that side of his mouth came into contact with something caustic/irritating. I don't really know. If he seems otherwise fine you can try giving him some Benadryl - 50mg (2 tablets) every 8 to 12 hours for a day or so. If no improvement then you should have your vet check him out.

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