# Cat Bump on the Paw Pad: Causes and When to Worry A cat bump on the paw pad is a lump on the thick, cushioned skin your cat walks on. Some are harmless, like a cyst or a callus from pressure. Others, like plasma cell pododermatitis or a tumor, need a veterinarian to diagnose and treat. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - A single small bump with no limping can often be watched for a few days, but any lump that grows, bleeds, or changes the way your cat walks needs a vet visit. - Plasma cell pododermatitis is a common inflammatory cause of swollen, soft, sometimes ulcerated paw pads, and it often affects more than one pad. - Silica (clay cat litter) can trigger granulomas in the paw pads, and these often show up as chronic swelling, ulceration, bleeding, or draining tracts, especially in the front paws [1]. - Limping, bleeding that will not stop, a foul smell, or a lump that keeps getting bigger are reasons to call your veterinarian promptly. - Do not try to pop, cut, or drain a paw lump at home. You can gently clean the area and keep your cat indoors while you wait for the appointment. ## What a Paw Pad Bump Looks Like and What Is Normal A normal paw pad is a thick pad of skin with a slightly rough, leathery surface. It should be smooth in outline, cool to the touch, and free of cracks, sores, or lumps. Cats have a large pad on the bottom of each paw plus smaller digital pads under each toe. A bump can be raised or flat. It can sit on the main pad, on a toe pad, or on the top of the paw. Owners often describe these as a cat has red bump on paw, a cat bump on top of paw, or a cat lump on paw. The location matters because the top of the paw and the area above the carpal pad (the small pad on the front of the wrist) can develop different problems than the walking surface. Some cats are born with extra or oddly placed pads. One report described a young cat with duplicated paw pads on the top of all four limbs, covered in thickened skin, with small nails between the pads [2]. That is a rare developmental finding, not a typical lump, but it shows that not every unusual pad shape is a disease. Paw pads also change with activity. In healthy cats, pad temperature rises after walking, which reflects normal blood flow during movement [3]. A warm pad is not automatically a sign of infection. A hot, swollen, painful pad is different and needs a closer look. ## Main Causes of a Cat Bump on the Paw Pad ### Plasma Cell Pododermatitis This is one of the most common inflammatory causes of paw pad lumps in cats. The pads become soft, puffy, and sometimes ulcerated. It often affects several pads, and the front paws are frequently involved. The surface can look pink or have a crumbly, waxy appearance. Many cats with this condition also have other skin or immune-related problems. ### Cysts and Follicular Lesions Cysts are fluid or debris-filled sacs under the skin. On a paw pad they feel like a firm or squishy pea. They can stay the same size for months. If a cyst ruptures, it may drain a thick material and look like an infection. ### Silica (Cat Litter) Granulomas Clay-based cat litter contains silica. In some cats, silica gets into small breaks in the paw pad skin and triggers a granulomatous reaction. A review of 13 paw biopsies from cats found chronic or intermittent pad swelling, ulceration, bleeding, or draining tracts, mostly in the front paws [1]. The foreign material in the biopsies matched the Raman spectra of several brands of silica-based cat litter [1]. Ten of the 13 biopsies also showed signs of plasma cell pododermatitis, which suggests the two conditions can occur together [1]. This is a strong reason to mention your cat's litter type to your veterinarian. ### Tumors and Growths Lumps on the paw can be benign or malignant. Benign growths include warts, sebaceous gland tumors, and harmless skin tags. Malignant tumors such as squamous cell carcinoma and mast cell tumors can also appear on the paw. Any lump that grows quickly, bleeds without trauma, or changes the pad's shape should be sampled. ### Hyperkeratosis and Calluses Hyperkeratosis means the outer skin layer is too thick. It can be inherited or acquired from repeated trauma, infection, cancer, or inflammatory skin disease [4]. A genetic form was identified in a dog with a variant in the GJB6 gene, which affects a skin structural protein [4]. In cats, thickened, cracked pads are more often linked to pressure, litter irritation, or inflammation than to a known gene. A callus is a thickened area from repeated pressure, and it can look like a bump. ### Foreign Bodies and Trauma A splinter, glass, thorn, or piece of hard litter can lodge in a pad and cause a lump with swelling. Cats that land hard or step on something sharp can also develop a bruise or abscess. These often hurt enough to cause limping. ### Infection Bacterial or fungal infections can create a swollen, painful pad. A draining tract or a bad smell points toward infection. Deep infections need veterinary treatment, not home drainage. | Cause | Typical clues | How urgent | |---|---|---| | Plasma cell pododermatitis | Soft, puffy, sometimes ulcerated pads, often several pads | See a vet soon, within days | | Cyst | Firm or squishy pea, stable size, no limping | Routine visit unless it grows or drains | | Silica (litter) granuloma | Chronic swelling, ulceration, bleeding, draining tracts, front paws [1] | See a vet soon | | Tumor | Growing lump, bleeding, shape change | Prompt visit, same week | | Hyperkeratosis or callus | Thick, cracked, rough pad surface [4] | Routine visit | | Foreign body or trauma | Sudden pain, limping, swelling, visible wound | Same day if limping or bleeding | | Infection | Redness, heat, pus, bad smell | Same day to urgent | ## Red Flags That Make It an Emergency Call an emergency clinic right away if you see any of these: - Bleeding from the paw that does not stop after 5 minutes of gentle pressure. - A deep cut, a nail torn off, or a pad that is partly detached. - Sudden severe limping, or your cat will not put the paw down at all. - A swollen paw that is hot, very red, or has a foul discharge. - A lump that has doubled in size in a few days. - Your cat is lethargic, not eating, or hiding more than usual. - You see a foreign object stuck in the pad that you cannot easily remove. A paw pad has a rich blood supply. That is why even small cuts can bleed a lot. Do not wait if bleeding continues. ## Safe Things You Can Do at Home While You Wait You cannot diagnose a paw lump at home, but you can keep your cat comfortable and prevent the problem from getting worse. - Keep your cat indoors. This limits dirt, litter, and rough surfaces on the paw. - Use a shallow, low-dust litter box. If you use clay litter, ask your vet whether a different substrate might help, since silica in clay litter has been linked to paw granulomas [1]. - Clean gently with warm water and a soft cloth. Do not scrub or use alcohol, hydrogen peroxide, or human antibiotic creams unless your veterinarian tells you to. - Check for foreign bodies in good light. Look between the toes and along the pad edges. If you see something embedded, do not dig for it. - Discourage licking. A cone or a soft collar can stop your cat from chewing the lump into an open sore. - Take a photo each day. Note the size, color, and whether it bleeds. This helps your vet see the trend. - Do not pop, squeeze, or cut the lump. This can spread infection and make a tumor harder to evaluate. If your cat is limping, keep them quiet and avoid stairs and jumping. If the limping is sudden and severe, treat it as an emergency. ## What Your Veterinarian Will Check and Test Your veterinarian will start with a full history. They will ask when you first noticed the bump, whether it has changed, whether your cat limps, and what litter you use. They will also ask about other skin problems, since paw disease can be part of a whole-body condition. The physical exam focuses on all four paws, not just the one with the lump. Your vet will compare the pads, check for swelling, ulcers, and draining tracts, and feel the lymph nodes. They will watch your cat walk. Gait matters because paw pad sensation helps control normal movement, and losing that feedback changes how a cat walks [5]. Common tests include: - Fine needle aspirate. A thin needle collects cells from the lump. This is quick and often done in the exam room. - Biopsy. A small piece of tissue is sent to a lab. This is the most reliable way to tell inflammation from cancer. - Skin scraping or cytology. This checks for infection, mites, or inflammatory cells. - Culture. A sample is sent to grow bacteria or fungi if infection is suspected. - Blood work. This checks overall health and looks for conditions that can affect the skin. - Imaging. X-rays or ultrasound may be used if a deep mass or bone involvement is suspected. If the lump is a cyst, your vet may drain it or leave it alone. If it is plasma cell pododermatitis, treatment often involves medication to calm the immune response. If it is a silica granuloma, removing the source and treating inflammation are key steps [1]. If it is a tumor, surgery or other treatment depends on the type and how early it is found. Doses for any medication are calculated by your veterinarian based on your cat's weight and health. Never give human pain relievers to a cat, since many are toxic. ## Prevention and Monitoring You cannot prevent every paw lump, but you can lower some risks. - Check your cat's paws weekly. Look at the pads, between the toes, and the top of the paw. Early lumps are easier to treat. - Keep the litter box clean. Scoop daily and change litter regularly. If your cat has repeated paw problems, discuss litter options with your vet [1]. - Trim nails carefully. Long nails can curl into the pad and cause pressure sores. - Watch for limping. A cat that shifts weight off a paw is telling you something hurts. Paw pad anesthesia alone changes walking patterns in cats, which shows how much they rely on paw sensation [5]. - Manage underlying skin disease. If your cat has allergies or an immune condition, follow your vet's plan. Uncontrolled skin disease can make paw problems worse. - Avoid rough surfaces. Hot pavement, sharp gravel, and icy sidewalks can injure pads. If your cat has a paw lump that comes and goes, keep a log. Note the date, size, and any bleeding or limping. Bring the log to your next visit. This kind of tracking helps your vet decide whether to watch, test, or treat. For related skin and paw concerns, see our guide to a [cat skin rash on paws](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-skin-rash-on-paws-causes). If your cat also has a wound from a scratch, read about [cat scratch infection risk](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-scratch-infection-risk). And if your cat is coughing or sneezing along with paw changes, those can point to a separate problem, so check our articles on [cat coughing](/knowledge/veterinary-medicine/parasitic-diseases/cat-coughing-when-to-worry) and [cat sneezing](/knowledge/veterinary-medicine/online-vet-and-care-costs/cat-sneezing-causes). ## Limitations and When to Contact a Veterinarian This article cannot tell you what your cat's lump is. Only a veterinarian can examine the tissue, run tests, and make a diagnosis. Individual cases need a veterinarian. Contact your veterinarian the same day if: - Your cat is limping or refusing to walk. - The lump is bleeding, draining, or has a bad smell. - The paw is swollen, hot, or very red. - Your cat is licking or chewing the paw constantly. - You see a foreign object in the pad. Go to an emergency clinic now if: - Bleeding will not stop after 5 minutes of pressure. - A pad is torn or partly detached. - Your cat is in severe pain, crying, or cannot bear weight. - The paw is cold, pale, or turning dark. - Your cat is weak, collapsed, or having trouble breathing. Schedule a routine visit if: - The lump is small, stable, and not painful. - Your cat is walking normally. - You want a baseline check and a plan for monitoring. Do not wait weeks to see if a paw lump goes away on its own. Some causes, like tumors, are easier to treat when found early. ## Frequently Asked Questions ### Should I worry about a small bump on my cat's paw pad? A small, stable bump with no limping is often not an emergency, but it still deserves a vet look. Cysts and calluses can stay quiet for a long time, while tumors and granulomas can start small and grow. If the bump changes size, bleeds, or causes limping, call your veterinarian. ### Can cat litter cause a bump on the paw pad? Yes, clay-based litter contains silica, and silica has been found in paw biopsies from cats with chronic swelling, ulceration, and draining tracts [1]. If your cat has repeated paw lumps, ask your vet whether changing litter might help. Do not switch litter suddenly without a plan, since litter changes can cause other issues. ### Is a red bump on the paw always an infection? No. Redness can come from inflammation, trauma, a cyst, a granuloma, or a tumor. Plasma cell pododermatitis often makes pads look pink and puffy. A red bump that is hot, painful, or draining is more likely to involve infection and needs prompt care. ### What if the bump is on top of the paw or above the carpal pad? Lumps on the top of the paw or above the carpal pad can be cysts, insect bites, foreign bodies, or tumors. They are less likely to be caused by walking pressure than pad lumps. Because the skin there is thinner, these lumps can ulcerate faster, so have your vet check them. ### Will my cat need surgery for a paw lump? Not always. Cysts may be drained or left alone, and inflammatory conditions are often treated with medication. Surgery is more likely for tumors, deep foreign bodies, or lumps that keep coming back. Your veterinarian will recommend the best option after examining the lump and any test results. ## Related Articles - [Cat Scratch: When to Worry About Infection or Rabies](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-scratch-infection-risk) - [Cat Sneezing: Common Causes and When to Worry](/knowledge/veterinary-medicine/online-vet-and-care-costs/cat-sneezing-causes) - [Cat Skin Rash on Paws: Causes and Home Care](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-skin-rash-on-paws-causes) - [Cat Coughing: When Should You Worry?](/knowledge/veterinary-medicine/parasitic-diseases/cat-coughing-when-to-worry) - [Cat Urinating Frequently: Causes and When to Worry](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-urinating-frequently-causes-when-to-worry) - [Cat Scooting: Causes and When to Worry](/knowledge/veterinary-medicine/preventive-and-routine-care/cat-scooting-causes-when-to-worry) - [Lump or Tumor on a Cat's Paw: Causes and When to Worry](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-paw-lump-tumor) - [Why Are My Cat's Paw Pads Cracked? Causes and Care](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/cat-cracked-paw-pads) - [Dry Paw Pads in Cats: Causes and Home Care](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/dry-paw-pads-in-cats) ## References 1. [Cutaneous silica-associated (cat litter) granulomas in the paws of 13 domestic cats](https://pubmed.ncbi.nlm.nih.gov/40652357/). Veterinary pathology, 2026. 2. [Dorsal duplication of paw pads in the four limbs of a cat](https://pubmed.ncbi.nlm.nih.gov/36855291/). Veterinary dermatology, 2023. 3. [Thermal imaging evaluation of the felines paw pad temperature before and after walking: A pilot study](https://pubmed.ncbi.nlm.nih.gov/40546894/). Veterinarni medicina, 2021. 4. [GJB6 missense variant in a Labrador Retriever with paw pad hyperkeratosis](https://pubmed.ncbi.nlm.nih.gov/41601192/). Animal genetics, 2026. 5. [Electrical Stimulation of Distal Tibial Nerve During Stance Phase of Walking May Reverse Effects of Unilateral Paw Pad Anesthesia in the Cat](https://pubmed.ncbi.nlm.nih.gov/36316008/). Motor control, 2023. ## Further Reading - [Merck Veterinary Manual: Cat Owners](https://www.merckvetmanual.com/cat-owners) - [Cornell Feline Health Center: Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)