My dog has a red lip spot growing like a cold sore. What could it be?
Hi there and thank you for using Petco Pet Education Center, formerly Petcoach to address your concern. Without seeing a picture of what you are describing it is difficult to say for sure what this could be. I suspect, due to Blue's age, that this could be a viral papilloma, histiocytoma or pimple-like growth. In all 3 cases, it should resolve on its own. It could be something other than these 3 possibilities. If the spot does not resolve or it worsens, I would recommend having a veterinarian examine Blue to that the most appropriate diagnostic and treatment recommendations can be made. I hope this helps guide you in the right direction! Please let me know if you have any other questions or concerns and I would be more than happy to help you further.
Updated on September 23rd, 2025