Help! My Dog Has a Bump that Keeps Coming Back! (Vet Answered)
This question has been answered by a vet
Veterinarian & Animal Behaviorist
With nearly two decades in veterinary medicine, Dr. Paola brings hands-on experience across multiple species. A graduate of the University of Guadalajara, she specializes in preventive care, animal welfare, and positive reinforcement training.
The Question
“Hey Dr. Paola,
My pitbull, Speedy, has a blister-like bump with hair missing in it, and sometimes it has stuff that leaks out. Sometimes she gets a allergy shot, and it dries up for a bit, but it doesn’t ever fully go away. What could it be? “ – Crystal
Quick Info about Speedy
Hi Crystal,
A small blister-like bump with hair loss that occasionally drains often comes from ongoing inflammation in the skin. Conditions such as a follicular infection, a localized hot spot, or a sebaceous cyst can look similar from the outside, almost like a tiny balloon that keeps refilling because the underlying trigger is still present. Since Speedy improves temporarily after an allergy injection, it suggests that itching and repeated licking or scratching may be keeping the area irritated, which is common in dogs with environmental allergies.
These bumps rarely resolve completely unless the underlying cause is identified and addressed. A veterinarian can examine the area closely, check for bacterial or yeast overgrowth, and determine whether cultures, cytology, targeted allergy management, or, in some cases, surgical removal would be the most effective approach. With an appropriate treatment plan, the skin can heal more predictably, and the cycle of irritation and drainage becomes far less likely to return.
Best,
– Dr. Paola