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My dog has a bump on her lip. Is it a cold sore or skin growth?
Updated on September 23rd, 2025
Pet's info: Dog | Mixed Breed Medium (23 - 60lb) | Female | spayed | 1 year and 7 months old | 40 lbs
I was wondering if dogs can get cold sores. My 1 year old pitbull mix has developed this sore on the outside of her lip over the course of 2 days. Do you have any idea of what it looks like? Thank you
4 Answers
Most Helpful Answer
Answered By Dr. Macartney, BVet Med, MRCVS
Veterinarian
Published on August 18th, 2017
From the pictures you have sent the "bump" appears to be a skin growth. There are several types off masses that can grow in the skin of dogs such as cysts, lipomas, allergic reactions and even some type of cancers. Some are benign and some are malignant, so careful observation is important, as well as having a vet examine it if you are concerned.
Since you only just noticed the lump, I would continue to monitor it for growth, ulceration, changes in texture or color. Measure the mass with a ruler so you can compare its growth in a weeks time. Rapidly growing masses are more concerning.
I hope that this answer was helpful and more importantly that Kylie feels better soon. Warmest regards to you both.
2Pet Parents found this answer helpfulRelated Answers from Veterinarians
Answered By Dr. B. DVM, DACVIM (Oncology)
Veterinarian
Published on January 24th, 2019
This appears to be a mass. A mass is a collection of cells. These cells can be benign (inflammation, etc) or more concerning (a tumor). There are some common skin tumors in dogs (some benign, some malignant) but as they can look the same way on the pet the best way to diagnose this is for your vet to perform a needle aspiration with cytology. This will be sent to a pathologist for diagnosis. Given that this is tricky location it is important to know what it is prior to trying to remove it (and with one type of skin tumor we may not recommend removal as they often resolve on their own). I hope this helps and thank you for using Petco Pet Education Center, formerly Petcoach!
14Pet Parents found this answer helpful
Answered By Linda G, MS, DVM
Veterinarian
Published on July 11th, 2019
Hello. This is probably a benign neoplasia called a lipoma, but any lump, bump or nodule that pops up, especially on an older dog, should be brought to your veterinarians attention as quickly as possible. Sometimes we will do a very simple needle aspirate to look for any unusual cells under the microscope, or your veterinarian may just elect to watch things. But it should at least be evaluated. Hope all is well & thanks for using Petco Pet Education Center, formerly Petcoach.
12Pet Parents found this answer helpful
Answered By Dr. Massimo Orioles, DVM, Cert AVP, MRCVS
Veterinarian
Published on May 19th, 2017
This kind of lump/growth needs to be ideally assessed by your veterinarian to have a definitive and specific answer. Usually there are two ways your vet can do that a part from examining it directly during physical examination. A biopsy can be taken under local or general anesthetic, otherwise a smaller sample through a fine needle can be aspirated (this technique is called FNA= fine needle aspiration).
Differentials include skin cysts, infections, benign or more sinister type of tumors.
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.7Pet Parents found this answer helpful