Hot Spots in Dogs: Causes, Treatment, and Prevention

Signs to watch for

• A clearly outlined area of red, swollen skin with hair loss
• A wet, shiny surface that oozes clear fluid or pus
• Matted or crusty hair stuck to the patch
• Constant licking, chewing, or scratching at one spot
• Pain when the area is touched, such as flinching, pulling away, or growling
• An unpleasant smell from the skin

Hot spots are most often found on the head and neck near the ears, on the hips and rump, near the base of the tail, and on the legs. They can appear anywhere, though. In a long or thick coat the sore can stay hidden under matted fur for a while. If your dog keeps going back to the same place, part the hair and look at the skin underneath.

Common causes

A hot spot almost always has a trigger. If the sore is treated but the trigger is missed, it often comes back. Common triggers include:

• Fleas and flea allergy, one of the most frequent causes
• Other allergies, such as environmental allergies or food allergy
• Ear infections, which lead to scratching around the head and neck
• Anal sac problems, which lead to licking and chewing near the tail
• A coat that stays damp after swimming, rain, or a bath
• Matted or dirty fur that traps moisture and heat against the skin
• Insect bites, small wounds, or skin irritation after clipping
• Joint or back pain, which some dogs respond to by licking the area
• Boredom or stress, which can lead to repeated licking

Dogs with thick undercoats or long hair are affected most often, because their coats hold moisture close to the skin. Golden Retrievers, Labrador Retrievers, German Shepherds, Newfoundlands, St. Bernards, and Rottweilers are among the breeds often mentioned. Hot spots can happen at any time of year, but they are more common in hot, humid weather, especially when dogs swim or get wet and are not dried well.

When to see the vet

A hot spot is rarely dangerous, but it is painful and can spread fast. It is best to have your vet look at it soon, ideally the same day or the next. Ask for an urgent appointment if the patch is growing quickly, if there are several patches, if your dog will not let you near it, or if it is close to an eye. The same goes for a dog that seems unwell in general, for example quiet or not eating well. Small pimples or bumps around the edge of the patch, or skin that feels thick and swollen, can mean the infection has gone deeper, so mention them to your vet. A sore that keeps growing or does not improve after a few days of treatment should be rechecked.

How vets diagnose and treat it

Most hot spots are recognized on sight. The bigger task is finding what started it. Your vet will usually check the coat for fleas, look inside the ears, check the anal sacs, and ask about recent swimming, grooming, and changes at home. They may press a slide or a piece of tape against the sore and look at the sample under a microscope. This shows what kind of bacteria or yeast are present. If hot spots keep coming back, your vet may suggest further tests, such as a bacterial culture or an allergy workup.

Treatment aims to heal the sore and stop the licking. Vets usually clip the hair around the hot spot so the skin can dry and the edges are easy to see. They then clean the area with an antiseptic. Because the skin is so tender, some dogs need sedation for this step. Hot spots are a surface skin infection, so in most cases they are treated with medicated washes, sprays, or creams. Your vet may also prescribe medicine to calm the itch and inflammation, and sometimes pain relief. Antibiotics by mouth are generally kept for infections that have gone deeper into the skin. A cone or a soft recovery collar stops your dog from reaching the spot while it heals. At the same time, your vet will look for the trigger and treat it, for example with flea control, ear treatment, or allergy management.

At home, keep the collar on for as long as your vet advises, even if your dog protests. Keep the area clean and dry, and use only the products your vet has given you. Ask before putting any other cream or spray on the sore, since your dog may lick it off or it may irritate the skin. Many hot spots clear up within 3 to 7 days of starting treatment. Deeper infections take longer, often several weeks. Finish the full course of any treatment and go back if the patch is not clearly better.

Spread to other pets and people

A hot spot develops from the dog's own skin bacteria and its own licking and scratching. The sore itself is not something other pets catch from your dog. Some triggers can spread, though. Fleas move easily between pets, and certain mites and fungal skin infections can pass to other animals and sometimes to people. Your vet can tell you whether this applies to your dog. If fleas started the problem, vets usually advise treating every dog and cat in the home and cleaning bedding and living areas as well. Washing your hands after touching or cleaning the sore is good everyday hygiene.

Preventing hot spots

Regular parasite control, as recommended by your vet, is one of the most useful steps, because fleas are such a common trigger. Brush your dog often to remove loose undercoat and mats, especially during shedding season. After swimming, rain, or a bath, dry the coat all the way down to the skin, and dry the ears well. Check the ears, the area under the tail, and the hips regularly, so you catch a red patch early. If your dog has allergies, ear infections, or anal sac trouble, work with your vet to keep them under control. Daily exercise and things to chew or sniff can cut down on boredom licking. Some vets suggest omega-3 fatty acids for dogs with itchy skin, so ask whether they would suit your dog.

Newly adopted dogs

Moving to a new home is a big change. A new routine and the stress of settling in can make some dogs lick and scratch more than usual. At Paw Squadron, the first stops after every rescue are the vet and a bath, with a checkup, deworming, and treatment against fleas and other parasites. Before adoption, every animal also gets a checkup, treatment, vaccinations, and a microchip. Once your dog is home, keep up the parasite prevention your vet recommends, learn how to brush and dry your dog's coat, and watch for any spot your dog keeps licking. For more guides on skin, coat, and everyday care, browse PawPedia. If you are thinking about adopting, the Adoptions page shows the animals waiting for a home.