My dog's bug bite turned into a black bump. What is it and what to do?

Thanks for using Petco Pet Education Center, formerly Petcoach! As dogs age, they can develop a variety of skin tumors, some benign (non-cancerous) and others cancerous. I do recommend all abnormal growths be evaluated by a veterinarian to determine if they are an issue or not. Many of these can be diagnosed with an analysis of a needle sample. Good luck!

I am sorry to hear about Rambo. The lumps we see here make me concerned he could have hives, or an allergic reaction to something. We often treat this with diphenhydramine (an antihistamine) and a steroid, in addition to bathing in case a topical allergen was encountered. If they are not hives we would be worried about a skin tumor, but without seeing your dog and getting an in depth history that is difficult to determine. Limping can be from a wide variety of problems ranging from an injury to a toe nail, a torn ligament, a fracture, a tumor, tick borne disease, and more. I would recommend getting Rambo in to the vet to address these issues and determine what is causing them to better guide treatment.

Thanks for the image. That could be an area of trauma or irritation. It may also be some localized infection (bacterial or fungal) or maybe a papillomatous growth (wart). If he is licking or chewing at the area, place an e-collar (cone) on him and schedule an exam with your veterinarian. If the spot is not bothering him and he is behaving normally otherwise, you can choose to monitor it at home for rapid change or growth, bleeding, discharge or discomfort. Should any of these symptoms develop, an exam with your veterinarian would be required to definitively diagnose the underlying cause. Any treatment will depend on the diagnosis.

Thanks for using Petco Pet Education Center, formerly Petcoach! This could be a benign or malignant growth. This could even be an abscess. There is no way of knowing what it is just based on its appearance. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have him evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good night!

This looks like it could be a growth and it's clearly bothering him if he's biting at it. Any suspicious lumps should be examined by the vet. The vet can perform a test called a fine needle aspirate on it. To do this, the vet sticks a small needle into the lump to get a sample of its cells, and examines the cells on a slide under a microscope. It's usually painless to the animal, and relatively quick to perform. Once the cause of the lump is diagnosed, the vet can discuss treatment options if needed. Give his vet a call to make him an appointment.

Given Rambo's age, it is less likely that he has a growth or mass of serious concern. However, without a fine needle aspirate or a biopsy of the lesion it is impossible to know. Given its appearance in the pictures, it looks like it was likely either some type of tumor or cyst that underwent too much pressure from fluid build up, and subsequently ruptured. In terms of treatment, you are doing most everything you can at home already. Some recommendations though: I would not use peroxide as this can actually delay the healing process I would not keep the area covered too closely or tightly as this can encourage reinfection I would instead place a cone or collar on Rambo to prevent licking or self-mutiation, as this still allows the area to be open to the air. In terms of what to do next or how to find out what you are seeing, you can do two different things. The first is simply wait and see what happens when the area heals. If it never grows back, great new! The second option would be to take him to the vet and try to obtain a sample for analysis. You can also wait to do this if you want when and if the lesion grows back.

This looks like it could be an insect bite or sting, or a tick bite if they are in your area. Skin infections can also occasionally start this way. If you start to see more lesions similar to the one above, or if this bump begins to increase in size or have any discharge I would recommend having it examined by your veterinarian. If it is an insect bite it should be gone in the next 7-10 days or so. Monster is a handsome guy!