A hot spot is a patch of skin your dog has licked, chewed or scratched until it turned raw, red and wet. Vets call it acute moist dermatitis or pyotraumatic dermatitis. It usually starts with something that itches or hurts, and the licking does the rest.
Hot spots grow fast. VCA's veterinarians describe owners who leave for work after noticing a pinpoint of redness and come home to a raw patch the size of a pancake. So the first job is to stop the licking (a cone works best). The second is a vet visit within a day or two, or right away if it's spreading or your dog seems sick.
What a hot spot looks like
Once you know the pattern, most hot spots are easy to recognize. Look for:
- a raw, red patch that is clearly worse than the skin around it
- wet, oozing skin, sometimes with pus and a yellow crust where the fluid dries in the hair
- hair loss over the patch, with matted, damp hair at the edges
- swelling and heat
- pain: your dog may flinch or pull away when you touch near it
- constant licking, chewing or scratching at that one spot
- a bad smell, especially if it's infected
Hot spots can hide. In long or matted coats, the patch may sit under the fur until it's already large, so part the hair anywhere your dog keeps licking.
Where hot spots show up
They can appear anywhere, but VCA lists the head, legs and hips as the most common sites. In a study of 44 dogs at one Swedish clinic, the cheek, neck and outer thigh came up most often.
The location often points to the trigger:
- Lower back or rump: think fleas and flea allergy.
- Behind the ear, on the ear flap or on the neck: think ear infection.
- Under or on top of the tail: think anal glands.
- Over a hip or ankle in an older dog: think pressure sores and sore joints that get licked.
Why hot spots spread so fast
It's a loop. Something makes the skin itch or hurt, and the dog licks. According to VCA, licking irritates the nerve endings in the skin, which makes it itch more, which brings more licking, biting and scratching. Vets call it the lick-itch-lick cycle.
Every round damages the skin a little more, and warm, moist skin lets the bacteria that normally live on the surface multiply. That's why the Merck Veterinary Manual files hot spots under surface pyoderma, a bacterial skin infection limited to the top layer. In the Swedish study, 25 of the 27 lesions that were cultured grew staph bacteria.
So a hot spot rarely fixes itself while the dog can still reach it.
What causes hot spots on dogs?
A hot spot is almost always a reaction to something else. The common triggers:
- Fleas and flea allergy, one of the most common starters. See our guide to flea allergy dermatitis.
- Allergies to things in the environment or to food. Atopic dermatitis is a frequent background problem.
- Insect bites.
- Ear infections. An itchy ear gets scratched, and a hot spot forms near it.
- Anal gland problems. Sore, full or infected glands lead to licking around the tail.
- A wet or matted coat. Swimming, baths or rain soak a thick coat that never dries properly. Mats trap water against the skin, and dogs bite at tangles until the skin breaks.
- Pain. Dogs lick sore joints, and older dogs with arthritis lie down a lot and get pressure sores.
- Boredom or stress. Bored dogs lick whatever is easy to reach, often the feet and forearms.
Which dogs get hot spots most?
Any dog can get one, but thick, dense or long coats hold heat and moisture against the skin. A board-certified veterinary dermatologist at MedVet lists Golden and Labrador Retrievers, Collies, German Shepherds, Saint Bernards, Akitas and Newfoundlands as higher-risk breeds. Cornell's Riney Canine Health Center adds dogs with drop ears, since wet ears invite ear infections.
Hot spots happen year-round, but warm, humid weather brings more of them. In the Swedish study (a single clinic in an area without endemic fleas), dogs aged 4 or younger and males were affected more often.
Is it a hot spot or something else?
Several skin problems look alike at a glance. Speed, texture and location usually tell them apart:
What you see | Likely | What sets it apart |
|---|---|---|
One raw, wet, red patch that appeared within a day or so and keeps growing | Hot spot | Sudden, moist, sharply outlined, usually one spot |
Small red bumps, pimples, crusts or rings of scale with patchy hair loss, often on the trunk | Many small spots rather than one wet patch | |
A raised, thickened, sometimes ulcerated patch on a lower leg, licked for weeks or months | Lick granuloma (acral lick dermatitis) | Slow, firm and thick instead of wet |
Crusted bumps and thin hair over the lower back, tail base and back of the thighs | Flea allergy | A pattern across the back end, not one patch |
Redness or a red-purple bump between the toes, with paw licking | On the feet, often a painful bump in the webbing |
These can overlap. Some hot spots sit on top of a deeper infection of the hair follicles: in the Swedish study, 20 of the 44 dogs had folliculitis under the surface when tissue samples were examined. That's one reason the vet looks closely instead of treating every red patch the same way.
Not sure what you're looking at? Our guide to common dog skin problems with pictures walks through more of them.
What to do right now
Until your dog is seen, your job is to protect the spot:
- Stop the licking. A cone (Elizabethan collar) is usually the best way to keep a dog off a hot spot. For a spot on the body, a snug T-shirt can work as a barrier.
- Keep it dry. A wet coat feeds hot spots, so skip swims and baths until your vet has seen it.
- Leave the hair to the vet. Don't trim around the spot with scissors. VCA warns it's easy to cut the skin by accident, and those cuts can need stitches.
- Don't put anything on it unless your vet tells you to.
- Call your vet and describe the size, where it is and how fast it grew.
Why home remedies often backfire
Online "home remedy" lists are where hot spots go wrong. Here's what the vet sources say about the usual suspects:
- Hydrogen peroxide damages healthy tissue. The Merck Veterinary Manual says it "is toxic to healthy tissue" and shouldn't be used to flush wounds.
- Soaps, rubbing alcohol, herbal mixes and tea tree oil are on VCA's list of things not to put on a wound unless your vet tells you to. Many of them slow healing.
- Essential oils can poison dogs. Concentrated essential oils should never go directly on a pet, and tea tree oil is the essential oil most often reported in pet poisonings, according to the Merck Veterinary Manual. Your dog will also lick off whatever you put on the spot.
- Human creams and medicines can be toxic to dogs. VCA advises asking your vet before using any medicine meant for people.
- Licking doesn't clean it. That's a myth, and on a hot spot, licking is the problem.
Some vets do let owners look after a small, uninfected hot spot at home. If yours does, they'll tell you what to use and how often. That decision belongs to your vet, not to a list online.
How your vet treats a hot spot
Treatment has two jobs: heal the patch and find the trigger. A typical visit looks like this:
- Clipping. VCA calls clipping the hair away from the hot spot and the skin around it "crucial." Air reaches the skin, the patch dries and medicine can actually touch it. It hurts, so some dogs need sedation.
- Cleaning and treating the skin. The vet disinfects it with an antiseptic such as chlorhexidine. Drying or soothing products work far better on clean, clipped skin.
- Medicine for itch and inflammation. Your vet may use a steroid, an antihistamine or another anti-itch medicine to break the cycle and ease the pain.
- Antibiotics when they're needed. Not every hot spot needs antibiotic pills. Merck says topical therapy alone usually treats surface and superficial skin infections, and saves oral antibiotics for deeper infections or the rare cases that don't respond. Your vet decides based on what they see, sometimes with a skin sample.
- The cone, usually until the skin heals.
- The trigger. Flea control, treating the ear infection or the anal glands, an allergy plan, pain relief, or more exercise and enrichment for a bored dog.
Your veterinarian chooses every product and dose based on your dog, the size of the hot spot and the cause. If they book a recheck, keep it, even if the spot looks better.
How to prevent hot spots
Hot spots come back when the trigger is never found, so prevention is mostly about the triggers:
- Keep flea control consistent all year, using the product your vet recommends.
- Check the ears for redness, moisture or discharge, and get ear infections treated early.
- Lift the tail at least once a week and look for redness or licked, stained hair. Cornell points out the first sore is easy to miss under a furry tail.
- Rinse and dry your dog fully after a swim. A towel may do for a short coat, but long or double coats may need brushing and a dryer.
- Brush often and remove mats so the skin can breathe.
- Manage allergies with your vet instead of waiting for the next flare.
- Give a bored dog more to do: walks, play, puzzle toys and training. If the licking looks compulsive, ask your vet about a behavior consult.
If your dog gets hot spots again and again, ask whether a referral to a veterinary dermatologist makes sense. MedVet's dermatologist suggests exactly that for frequent repeat cases.
When to call the vet
A Texas A&M veterinary dermatologist advises having a hot spot checked by a veterinarian right away to stop a deeper infection.
- Call now: the patch is spreading fast or new ones are appearing, there is pus, or your dog is in a lot of pain or seems sick (tired, off food, hiding).
- See your vet within a day or two: a small hot spot, even one that looks minor. Put the cone on in the meantime.
- Mention it at your next visit: your dog has had hot spots before and you want a plan to prevent the next one, or there's a spot your dog keeps licking but the skin still looks normal.
Quick answers
Will a hot spot go away on its own? Rarely. As long as your dog can reach it, the lick-itch-lick cycle keeps it going, and it tends to get bigger.
Why does my dog keep getting hot spots? Usually because the trigger is still there: fleas, allergies, ear infections, anal glands, a wet coat or boredom. Finding and treating that cause is what breaks the pattern.
Originally written by Jaclyn. Updated by the I Love Veterinary editorial team.
Sources
- Merck Veterinary Manual: Pyoderma in Dogs and Cats
- Merck Veterinary Manual: Pyoderma in Dogs (owner version)
- VCA Animal Hospitals: Hot Spots in Dogs
- VCA Animal Hospitals: Wound care dos and don'ts
- Texas A&M College of Veterinary Medicine: Does your pet have a hot spot?
- MedVet: Hot Spots in Dogs: What They Are and How to Treat Them
- Cornell Richard P. Riney Canine Health Center: Hot spots
- Holm BR et al. A prospective study of 44 cases of pyotraumatic dermatitis. Veterinary Dermatology, 2004
- Reinke SI et al. Histopathologic features of pyotraumatic dermatitis. JAVMA, 1987
- Merck Veterinary Manual: Initial Wound Management in Small Animals
- Merck Veterinary Manual: Toxicoses From Essential Oils in Animals
- Shumaker AK. Diagnosis and Treatment of Canine Acral Lick Dermatitis. Veterinary Clinics of North America, 2019
- Merck Veterinary Manual: Flea Allergy Dermatitis in Dogs and Cats
- Merck Veterinary Manual: Interdigital Furunculosis in Dogs
This article is for general information and is not a substitute for advice from your veterinarian.
