Sores on your dog’s paws most often come from allergies and the secondary infections that follow. Environmental allergies (atopic dermatitis) and food sensitivities are the leading causes seen in both primary care and specialist veterinary dermatology practices. But the list of possibilities is long, ranging from bacterial and fungal infections to parasites, physical injuries, and occasionally serious internal disease. Understanding the pattern, location, and appearance of the sores can help narrow down what’s going on.
Allergies Are the Most Common Cause
The paws, especially the front feet, are one of the most frequently affected areas in dogs with atopic dermatitis. The first sign is usually itchiness: your dog may lick, chew, or gnaw at the paws persistently. Over time, that constant moisture and self-trauma breaks down the skin, creating raw spots, redness, and open sores. You might also notice a rust-brown discoloration of the fur around the paws, which is saliva staining from obsessive licking and often signals a yeast overgrowth underneath.
Food sensitivities cause the same pattern. The distinction between environmental and food allergies is difficult to make based on appearance alone, which is why vets often recommend an elimination diet trial lasting several weeks to rule food in or out. Contact dermatitis, where the paws react to something they physically touch like lawn chemicals, road salt, or cleaning products, is another possibility, though less common.
The critical thing about allergic paw sores is that they rarely stay “just allergies.” Broken, inflamed skin is an open invitation for bacteria (most commonly a staph species called Staphylococcus pseudintermedius) and yeast. These secondary infections make the sores worse and harder to resolve, which is why treating the allergy alone without addressing infection, or vice versa, often fails.
Bacterial and Yeast Infections
Bacterial infections on the paws range from mild surface-level problems to deep, painful lesions. Superficial infections may look like small pustules, redness, or crusting between the toes. Deep infections are more serious and can produce swollen, oozing nodules that your dog can barely walk on.
Yeast infections, particularly from an organism called Malassezia, have a distinctive profile. The skin becomes greasy or waxy, sometimes with a yellow or slate-gray scaling, and there’s usually a strong, unpleasant odor. One telltale sign is dark brown discoloration around the nail beds, sometimes accompanied by compulsive paw chewing. Yeast thrives in the warm, moist folds between your dog’s toes, making the paws one of its favorite locations.
Interdigital Furuncles (Bumps Between the Toes)
If the sores look like firm, red, swollen bumps between your dog’s toes rather than flat rashes or raw patches, they may be interdigital furuncles. These are deep infections, not cysts, despite sometimes being called “interdigital cysts.” They form when hair follicles between the toes get damaged, usually from the mechanical pressure of walking. The follicle ruptures under the skin, releasing keratin (the protein that makes up hair) into surrounding tissue. Since keratin is highly irritating when it’s loose in the skin, this triggers an intense inflammatory reaction, and bacteria pile on top of that.
Certain breeds are more prone to this problem, particularly short-coated, heavy-bodied dogs whose foot conformation pushes the toes together and drives hairs back into the skin. English Bulldogs, Labrador Retrievers, and similar breeds deal with this frequently. The frustrating part is recurrence: even after treatment clears the infection, residual keratin fragments in the tissue can reignite the whole cycle.
Parasites That Target the Paws
Demodectic mange has a form that specifically targets the feet, called demodectic pododermatitis. Demodex mites burrow into hair follicles and cause hair loss, thickened skin, and secondary bacterial infections. When generalized mange is being treated elsewhere on the body, the feet are often the last area to clear up because the mites seem to hold on longest there. Old English Sheepdogs and Shar-Peis are particularly prone to severe forms.
Hookworm larvae can also penetrate the paw pads and skin between the toes, causing irritation and sores, especially in dogs housed on contaminated soil or gravel. Harvest mites (chiggers) and ticks can cause localized inflammation on the feet as well.
Physical and Environmental Injuries
Sometimes the cause is straightforward: your dog’s paws got hurt. Hot pavement is a major culprit in summer. On a day when the air temperature is just 86°F, asphalt surfaces can reach 135°F, hot enough to burn paw pads in 60 seconds. These thermal burns cause blistering, peeling, and raw, painful sores on the pads.
Rough terrain, ice, sharp gravel, thorns, and chemical irritants like de-icing salts can also crack, cut, or blister the paw pads. Foreign bodies, such as a grass awn (foxtail) embedded between the toes, can create a draining sore that won’t heal until the object is removed. If your dog suddenly develops a single painful sore on one paw, a foreign body or puncture wound is a likely explanation.
Autoimmune and Internal Disease
Less commonly, paw sores signal something happening inside your dog’s body. Pemphigus foliaceus, an autoimmune skin disease, can target the paw pads specifically. It causes severe thickening and overgrowth of the pad surface, along with peeling, cracking, fissuring, and ulceration along the pad margins. The pads may look almost villous, with an abnormal, rough, shaggy texture.
An even rarer condition called hepatocutaneous syndrome links liver disease to severe paw pad lesions. Dogs with this disorder develop crusting, reddened skin lesions on the pads alongside a distinctive pattern of liver damage and amino acid deficiency. The paw pads may crack deeply and ulcerate. This condition is serious and requires ongoing monitoring and treatment of both the skin and the underlying liver problem.
These causes are uncommon, but they’re worth knowing about because they look different from typical allergic or infectious sores. Paw pad lesions that are unusually thick, deeply cracked, or that affect all four feet symmetrically without much itching warrant a closer veterinary look.
How Vets Figure Out the Cause
Because so many different problems look similar on the paws, diagnosis usually involves a few targeted tests. Skin scraping checks for mites. Cytology, where a sample from the sore is examined under a microscope, can quickly identify whether bacteria or yeast are present and whether the infection is superficial or deep. If infections keep coming back, a bacterial culture helps identify the specific organism and which treatments will work against it.
For suspected allergies, the process is longer. Your vet may recommend a strict elimination diet for several weeks to test for food sensitivities, followed by allergy testing (blood or skin-prick tests) for environmental triggers. In some cases, especially when sores are chronic and not responding to standard treatment, a small tissue biopsy is needed to check for autoimmune disease or unusual infections.
What to Do at Home (and What Not To)
If your dog has a minor paw wound that’s bleeding, apply gentle direct pressure with a clean, dry cloth or gauze and keep it covered during transport to the vet. Resist the urge to apply hydrogen peroxide, rubbing alcohol, tea tree oil, or antibiotic ointments unless your vet specifically tells you to. These products can interfere with healing or irritate already damaged tissue.
For ongoing paw sores, keep the area clean and dry. Moisture between the toes fuels both bacterial and yeast growth, so drying your dog’s feet after walks in wet weather helps. An Elizabethan collar (cone) or protective booties can break the lick-chew cycle that makes allergic paw sores progressively worse.
Watch the discharge. If a wound continues to produce bloody, green, or yellow fluid for several days, that signals the infection isn’t resolving. Sores that are spreading, deepening, causing your dog to limp, or accompanied by swelling between the toes generally need professional treatment rather than a wait-and-see approach.