Your kitty's swollen paw may result from several different causes, so determining the underlying reason is essential to successful treatment. Although most reasons for paw swelling are treatable, it's often hard to spot a swollen paw in a cat, since they tend to hide injuries really well. If you see your cat limping, favoring one paw over another, or licking or chewing at their paw(s), this is your cue to examine it more closely for signs of a problem, like swelling or discharge.
Why Do Cats Have Swollen Paws?
A swollen paw is a sign of an underlying problem. Once you figure out what's causing the swelling, you can begin the proper treatment. There are a few common reasons for swelling in your cat's paw.
Overgrown Toenails/Claws
Even though cats groom themselves meticulously, sometimes their claws become overgrown and puncture the soft pads on the underside of their toes or paw. This painful condition can progress to a localized infection. Fortunately, overgrown claws are easily treated. Your veterinarian can clip the overgrown claw and address the injured portion of the paw or paw pad. This may require your cat to be lightly sedated. Overgrown toenails are the leading cause of swollen paws in cats.
Bee Stings
Bess stings are more common in outdoor cats, but indoor cats can be affected as well. Although a bee sting can rapidly cause swelling, it usually isn't too painful. Cats are generally more likely than dogs to be stung on their paws because of their tendency to swat at bugs.
A bee sting causes an allergic reaction and, in uncomplicated cases, the swelling should go down within 24 hours. If a secondary infection develops, the swelling can persist and progress. If this happens, your cat should be evaluated by your veterinarian.
Other Stings or Bites
Stings or bites from arachnids, like spiders and scorpions, can produce remarkable swelling, pain, and cause severe tissue necrosis. For example, a bite by a brown recluse spider produces a slowly healing open wound that can progress to death of surrounding tissue due to lack of blood supply or overwhelming infection. If the spider's venom enters the bloodstream, this can cause illness including vomiting, fever, bleeding problems, and even kidney or liver damage. These complications can be fatal, so be sure to contact your veterinarian if you are concerned your cat came into contact with an arachnid.
Punctures and Other Tissue Trauma
If your cat steps on something sharp or pointy, it can puncture the skin and produce a wound that may become infected. These swellings are often painful, depending on the stage the infection is in.
Pododermatitis
Pododermatitis refers to inflammation of the skin between the toes, nails or nail beds, or paw pads. Causes of pododermatitis include anatomical malformations, trauma, allergic disease, bacterial or yeast infection, immunosuppression, and parasites. Cats also develop a specific form of pododermatitis called plasma cell pododermatitis ("pillow foot") which is an immune-mediated disease. Pododermatitis results in swelling, pain, fluid retention, redness, or itching. Your vet may need to perform a biopsy of the affected tissue to determine the underlying cause of pododermatitis and the best treatment plan.
Fracture
If your cat breaks a bone in its paw, this may cause painful swelling. Take your pet to the vet immediately if you're not sure.
Treatment
Call your veterinarian as soon as you notice any swelling on your cat's paw or elsewhere. Until your cat has been examined by your vet, don't attempt to give it any medications. Cats are very sensitive to painkillers like aspirin, and giving your cat acetaminophen, such as Tylenol, can be fatal. Never give over-the-counter or unused portions of prescriptions to your pet.
Your veterinarian will administer or recommend medications to help reduce the swelling and stop the allergic reaction if it's the result of a bee sting or other allergen. Some infections require a course of antibiotics or application of antibiotic ointment. If an abscess has formed, it may need to be lanced and drained.
If your vet suspects a broken bone, they will X-ray your cat's paw to confirm. Depending on the location of the break, the vet may set the bone in a splint. In some cases, surgery is necessary to repair the break.
If your cat is treated for wounds on the bottom of its paws, ask your vet about switching from a clay-based pelleted litter to shredded paper until the wounds heal to help keep your cat's paws clean and prevent reinfection of the swollen area.
Prevention
If your cat repeatedly suffers from ingrown or overgrown nails, enlist help in learning how to trim your cat's claws. Keeping your kitty's claws neatly trimmed will eliminate overgrown-nail issues. Regularly inspect your outdoor cat's paws for signs of burrs, stings, bites, or cuts. Treating problems early may help prevent the types of issues that lead to inflammation.
Some older cats or cats with medical conditions, such as arthritis, are less mobile and not inclined to do the necessary clawing that keeps their nails in shape. If your cat is a senior and you are uncomfortable trimming its claws by yourself (which is totally understandable), take it to a reputable groomer or your veterinarian's office.
Keep the area where your cat spends most of its time free of anything that you think could potentially cause an injury. To prevent injuries to your cat's paw pads, keep it away from sharp objects or toys (Legos are a particular bane for kitty feet) or rough surfaces where it may injure itself. If your cat tends to jump up on your kitchen countertops, be especially careful when using your stove-the stovetop stays hot for a long time after you're done using it, so keep the burners covered until they have cooled down.
If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.