Veterinarians and veterinary team members sometimes throw this term around. Here’s some info on what is and isn’t a “hot spot” when it comes to the condition of your dog’s skin.
What’s a hot spot?
In medical jargon, a hot spot is called pyotraumatic dermatitis. True hot spots are patches of very inflamed, painful and moist skin. They can develop rapidly—sometimes in less than an hour—as a result of intense scratching. As the inflamed skin oozes, the surrounding hair sticks tight over the area, creating an ideal environment for bacteria to grow. Last but not least, that bacteria can make a foul odor. But hot spots aren’t caused by that stinky bacteria— they’re typically a result of allergy or anything else that causes your dog to scratch intensely at one location.

Two ruptured pustules
What’s the difference between hot spots and pustules?
Pustules are smaller, less painful, less smelly and less obvious than hot spots. In most cases, pustules are caused by bacterial infection in or on the skin. Pustules typically start very small and are difficult to see. Compared to human pimples, canine pustules are easily broken and rarely seen. When pustules break, the bacteria and debris spill out. As this material dries, it forms a crust that traps the surrounding hairs and irritates the skin, causing a roughly circular ring of redness. When the crust falls off, it takes the hair with it, leaving a small, but obvious, hairless area. Pustules often result in itching but are rarely painful.
How will my veterinarian treat hot spots or pustules?
Hot spots must be cleaned gently with an antiseptic in the veterinary hospital. The hair surrounding the hot spot usually needs to be shaved to prevent it from covering the wound and becoming matted with discharge. The pain can be so bad that your dog must be sedated prior to cleaning. After cleaning, the veterinarian will typically prescribe an oral antibiotic. Oral pain relievers and anti-inflammatory drugs might be given as well. In contrast, pustules are often treated at home with an antiseptic shampoo. Oral antibiotics may be necessary, depending on your pet’s medical history and how bad the pustules are. Whether pustules or hot spots are giving your dog a hard time, your veterinarian should investigate the cause to reduce the chance they’ll pop up again. Allergic dermatitis is the most common underlying cause of both pustules and hot spots.
What should I be watching for at home during treatment?
Whether it’s hot spots or pustules that your veterinarian is helping to treat, you should see a reduction in itching and discomfort. If there was a foul odor, it shouldn’t return. If new spots develop, you should call your veterinarian immediately.
What follow-up is needed?
A follow-up exam at your veterinarian’s clinic is an important part of the treatment plan. During the visit, your veterinarian will determine whether the infection has resolved or new hot spots and pustules are popping up. If your dog’s pain and discomfort is under control, this visit might be the perfect time to investigate the underlying cause of the hot spot or pustules.