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My guinea pig has a growing lump on his neck. What should I do?

Updated On September 23rd, 2025

Pet's info: Small Animal | Guinea Pig | Male | unneutered

Hello, I recently got two new guinea pigs last Monday. They are both males and are a few months old. I realized the day I got them, one of the boys had a little hard lump on his neck. I thought he got into something, but it keeps getting bigger by the day and he doesn’t seem uncomfortable. He is eating and letting me play with him, I’m just concerned because it’s getting big..

1 Answer

Most Helpful Answer

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Answered By Todd Cecil

Veterinarian

Published on January 30th, 2019

Thanks for reaching out about Chim Chim. The pet store should be contacted as if the swelling is on the ventral neck, it is likely an enlarged lymph node and a condition termed "caseous lymphadenopathy" or strangles. Systemic antibiotics are needed, possible lancing of abscess. It is contagious to other guinea pigs. A veterinary visit is recommended, soon, before he stops eating.

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