Dog Skin Sores: Causes, Home Care, and When to See a Vet

Name: Dog Skin Sores: Causes, Home Care, and When to See a Vet
Creator: Dr. Zubair Khalid

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-10-03

Dog skin sores are breaks in the skin that can look like red patches, scabs, oozing spots, or open wounds. They have many causes, from allergies and infections to injuries and pressure points. Some heal with simple home care, and some need a veterinarian quickly.

This article is educational and is not a substitute for veterinary diagnosis or treatment.

Quick Answer

A sore that is small, clean, and not spreading may be safe to monitor at home for a day or two, but any sore with pus, odor, or fast growth needs a vet visit.
Do not use human antibiotic creams, steroid creams, or hydrogen peroxide on dog skin sores unless your veterinarian tells you to.
Licking is the most common reason a minor sore becomes an infected sore, so blocking access with a cone or cover matters.
Bacterial skin infections in dogs are often caused by Staphylococcus species, and some are resistant to common antibiotics [1].
Deep or widespread infections can become life threatening, so early veterinary care is safer than waiting [2].

What Dog Skin Sores Look Like and What Is Normal

A skin sore is any area where the surface of the skin is broken or damaged. You might see a red raw patch, a scab, a crusty spot, a small ulcer, a bump that has opened, or a moist area where hair has rubbed away.

Normal skin in dogs is smooth, flexible, and covered by hair in most breeds. It should not have a strong smell, and your dog should not be constantly licking, chewing, or scratching one spot.

Dermatitis is the general term for skin inflammation, and it can show up as itching, scaling, redness, thickened skin, darkening, odor, oiliness, or hair loss [3]. The usual path of a skin disease starts with a trigger that leads to boils, scabs, scales, or blisters [3]. Sores are often the visible result of that process, not the original problem.

Some sores are superficial, meaning they sit in the top layers of skin. Others are deep, meaning they extend into the lower layers. Deep infections tend to be more painful and more serious.

Common Causes of Dog Skin Sores

Many different problems can produce sores on a dog's skin. The table below covers the most common ones and how urgent each tends to be.

Cause	Typical clues	How urgent
Bacterial skin infection (pyoderma)	Pus, crusts, red bumps, bad odor, spreading under the hair	See a vet soon, same week
Allergies (including atopic dermatitis)	Itching, licking, redness, sores in armpits, paws, ears, or groin	Routine visit, sooner if infected
Hot spots (acute moist dermatitis)	Sudden wet, red, painful patch that grows fast	See a vet within a day or two
Parasites (fleas, mites, mange)	Scratching, hair loss, scabs, sores along the back or ears	Routine visit, sooner if severe
Trauma or foreign object	A cut, puncture, or swelling after a walk or play	Same day if deep or bleeding
Pressure sores	Sores over elbows, hips, or heels in dogs who lie down a lot	Routine visit, sooner if open or draining
Skin ulcers	Crater-like wounds that may ooze or bleed	See a vet, these need a diagnosis
Whole-body disease	Sores plus weight loss, appetite change, or lethargy	Same day

Bacterial skin infection, called pyoderma, is one of the most common reasons dogs get sores. It is usually caused by Staphylococcus species that normally live on the skin but take over when the skin barrier is damaged [1]. In one study of confirmed staphylococcal pyoderma cases, about 63 percent were single-organism infections and about 37 percent involved more than one type of bacteria [1]. Mixed infections were linked to recurrent disease, longer duration, tissue invasion, and allergic skin disease [1].

Allergies are a frequent trigger. Atopic dermatitis is a common chronic, itchy, inflammatory skin disease in dogs, and it can lead to repeated skin infections [4]. Dogs with allergies often develop sores in the same places over and over, such as the paws, ears, belly, and around the eyes. If your dog has ongoing itching along with sores, see Dog Itchy Skin: When to See the Vet and How to Help.

Skin ulcers are a specific type of sore that looks like a crater or a punched-out area. They can come from infections, pressure, immune disease, or poor blood flow. If the sore looks like a hole instead of a scrape, see Dog Skin Ulcers: Causes, Treatment, and When to See a Vet.

Nutritional problems can also affect the skin, though this is uncommon in dogs eating modern, balanced diets [5]. Siberian Huskies and a few other breeds may need extra zinc in the diet, so ask your veterinarian before adding supplements [5].

Red Flags That Make It an Emergency

Some sores are minor. Others are a sign that something serious is happening. Get emergency care right away if you see any of these.

The sore is spreading quickly, doubling in size within hours.
There is pus, a foul odor, or green or yellow drainage.
The skin around the sore is hot, swollen, or turning dark.
Your dog is limping, crying out, or pulling away when touched.
Your dog is lethargic, not eating, vomiting, or breathing fast.
There is bleeding that will not stop.
The sore is deep enough that you can see tissue underneath.
Multiple sores appeared at once across the body.

Deep or widespread pyoderma can become life threatening. One reported case involved a dog whose skin infection spread throughout the body and led to septic shock and death despite treatment [2]. That case also shows how hard mixed and resistant infections can be to treat [2]. Early veterinary care gives your dog the best chance.

Safe Home Care for Dog Skin Sores While You Wait

Home care is about keeping the area clean, protecting it, and preventing your dog from making it worse. It is not a substitute for a diagnosis.

Clean gently

Use plain warm water or a diluted pet-safe antiseptic cleanser that your veterinarian recommends. Gently wipe the sore once or twice a day. Do not scrub, pick at scabs, or use alcohol, hydrogen peroxide, or human antibiotic ointments unless your vet tells you to. These can damage healing tissue and hide the true problem.

Stop the licking

Licking sores on dogs is one of the biggest reasons a small problem turns into an infected sore. Dogs have bacteria in their mouths, and constant moisture softens the skin. Use an Elizabethan collar, a soft cone, or a medical recovery suit. Keep it on until the sore is fully closed, not just when you are watching.

Keep the area dry

Moisture feeds bacteria. After cleaning, pat the area dry with a clean cloth. If your dog has skin folds, gently dry between them. Change bedding often, and keep your dog out of ponds, pools, and muddy areas until the sore heals.

Cover if needed

A clean, loose bandage can protect a sore on a leg or paw. Change it daily and check for odor, moisture, or swelling. Do not wrap tightly. If the bandage gets wet or dirty, replace it.

Do not start antibiotics on your own

Never give your dog leftover or human antibiotics. Bacterial resistance is a real problem in canine skin infections. In one study, both major Staphylococcus species showed high resistance to certain beta-lactam antibiotics and third-generation cephalosporins [1]. Your veterinarian needs to choose the right drug based on your dog's specific infection.

Watch for change

Take a photo each day with your phone so you can compare. Note the size, color, smell, and whether your dog is licking more or less. This record helps your vet decide how urgent the problem is.

If the sore looks infected, see Dog Skin Infection: When to See a Vet vs. Home Care.

What Your Veterinarian Will Check and Test

Your veterinarian will start with a full history. They will ask when the sore appeared, whether your dog is licking or scratching, what food and flea prevention you use, and whether this has happened before.

Next comes a physical exam. Your vet will look at the whole body, not just the sore, because skin problems often show up in several places. They will check the ears, paws, belly, and skin folds. They may also check for enlarged lymph nodes or signs of pain.

Common tests include:

Skin scrapings to look for mites under a microscope.
Cytology, where a sample of pus or crust is examined for bacteria and yeast.
A tape prep or impression smear to identify organisms on the surface.
Bacterial culture and sensitivity testing for deep, recurrent, or resistant infections.
Blood work if whole-body disease is suspected.
Allergy testing or a diet trial if allergies are the likely trigger.

Your vet may also use a severity scoring approach. One proposed system for superficial pyoderma counts papules, pustules, epidermal collarettes, and crusts, then combines that with a clinician's overall severity rating [6]. This kind of tracking helps measure whether treatment is working [6].

Treatment depends on the cause. Bacterial infections usually need antibiotics, and your veterinarian calculates the dose from your dog's weight and health. Medicated shampoos, sprays, or wipes may be part of the plan. Allergies need a longer-term strategy, not just a short course of pills. Deep infections may need longer treatment and repeat checkups.

Preventing and Monitoring Dog Skin Sores

Prevention starts with the basics.

Keep up with flea, tick, and mite prevention all year.
Feed a complete, balanced diet. Ask your vet before adding supplements [5].
Bathe your dog with a gentle pet shampoo, and dry the coat well.
Check the skin weekly, especially in dogs with allergies or skin folds.
Keep allergies under control. Uncontrolled itching leads to scratching, then sores, then infection.
Provide soft bedding and turn or reposition dogs who lie down for long periods.
Trim nails so scratching does less damage.
See your vet early when a new sore appears, before it spreads.

If your dog has a history of skin infections, ask your veterinarian how often they want to recheck. Recurrent or mixed infections often need a longer plan and sometimes a culture to guide treatment [1].

Limitations and When to Contact a Veterinarian

Home care cannot diagnose the cause of a sore. It can only keep the area clean and protected until you get professional help. Individual cases need a veterinarian, because the same-looking sore can have very different causes and treatments.

Contact your veterinarian the same day if you see pus, odor, spreading redness, a sore that is getting bigger, or a dog who is licking constantly. Go to an emergency clinic now if your dog is lethargic, not eating, bleeding heavily, has a deep wound, or has many sores appearing at once. A routine visit is fine for a small, stable sore that is not infected and not bothering your dog, but do not wait more than a few days if it is not improving.

Frequently Asked Questions

Should I put antibiotic cream on my dog's sore?

No, do not use human antibiotic creams unless your veterinarian prescribes them. Some ingredients are not safe for dogs, and these products can mask the real problem. Your vet will choose a product and dose based on your dog's weight and health.

Why does my dog keep licking its sore?

Licking is an instinct that soothes itching and pain, but it also keeps the skin wet and adds bacteria. That cycle makes the sore worse and can turn a minor scrape into an infected sore. A cone or recovery suit breaks the cycle while the skin heals.

How long does a dog skin sore take to heal?

It depends on the cause. A small scrape may close in a few days, while a bacterial infection often needs weeks of treatment. Deep infections take longer and may need repeat checkups. Your veterinarian will give you a timeline based on what they find.

Can I use hydrogen peroxide to clean a dog sore?

No, hydrogen peroxide can damage healing tissue and slow recovery. Use plain warm water or a pet-safe cleanser your veterinarian recommends. Gentle cleaning once or twice a day is enough.

When should I worry about a sore that smells bad?

A bad smell usually means infection, and it needs a vet visit soon. Odor often comes with pus, crusting, and spreading redness. Do not wait for it to clear on its own, because some skin infections can become serious quickly.

References

Antimicrobial resistance and epidemiological determinants of single and polymicrobial staphylococcal infections in canine pyoderma. Acta veterinaria Hungarica, 2026.
Microbiological and clinical aspects of complicated canine pyoderma: A case report. Open veterinary journal, 2026.
Dermatitis and Dermatologic Problems in Dogs - Dog Owners. Merck Veterinary Manual.
Systemic Inflammation in Dogs With Atopic Dermatitis Compared to Healthy Dogs and Dogs With Pemphigus Foliaceus: A Study Using a Limited Cytokine Panel. Veterinary dermatology, 2026.
Whole-body Disorders that Affect the Skin in Dogs - Dog Owners. Merck Veterinary Manual.
Standardising Assessment of Superficial Pyoderma in Dogs: Proposal of a Severity Score. Veterinary dermatology, 2026.