Swollen Paws and Legs in Cats

If you notice that your cat has a swollen leg or paw—or worse yet, all of their legs and paws are swollen—you are no doubt wondering what to do, and probably worried if they’ve broken something. Here’s everything you need to know about swollen paws and legs in cats.

What To Do if Your Cat’s Paw or Leg Is Swollen

The first thing to do is to check their overall well-being. If any of the following are true, see a veterinarian immediately, because you could be dealing with an emergency situation:

• The swelling is severe

• All of your cat’s legs or feet are swollen

• Your cat is in a lot of pain (hiding, won’t let you touch them, vocalizing, or aggression)

• You know that your cat has been hit by a car, attacked by a dog, or had another major trauma

• You see evidence of a serious injury, like bleeding, limb dragging, or an obviously broken bone or dislocated joint

• Your cat has other worrisome symptoms, like trouble breathing, disorientation (confusion), weakness, or extreme lethargy (tiredness)

On the other hand, it’s unlikely that you are dealing with an emergency if your cat’s leg or paw swelling is relatively mild and isn’t having a big effect on their movement, energy level, comfort, and appetite. Be careful if you decide to examine your cat, as touching a swollen area may hurt them.

As long as the swelling is minor and your cat seems fine otherwise, it’s okay to give it a day or two to see if it will get better on its own. But if it doesn’t, make an appointment with your veterinarian. In the meantime, keep your cat indoors, encourage them to rest, and monitor them closely. Get them to a vet quickly if things get worse.

What Causes Swollen Cat Paws and Legs?

Cats can develop swollen paws and legs for many reasons. It’s helpful to divide possible causes into three groups. These categories can overlap, but they can help narrow down the most likely causes of a cat’s swollen legs or paws. The descriptions that follow are simplified, since swellings often develop in many ways.

When all of a cat’s legs or paws are swollen, a “whole-body” problem is likely. Possibilities include:

• Heart disease: The normal flow of blood can be slowed by heart disease, which leads to fluid leaking out of blood vessels and tissue swelling.

• Liver disease: The liver makes albumin (a type of protein) that helps keep fluid in blood vessels. Advanced liver disease can lead to low blood albumin levels and swelling.

• Kidney disease: Cats with kidney disease may lose albumin in their urine, which makes it more likely that fluid will leak out of blood vessels and into the surrounding tissue.

• Systemic infections: Bacterial, viral, fungal, and other types of infections can make blood vessels inflamed and leaky, leading to swelling. Cats may also develop swollen lymph nodes in response to infections.

• Some types of drugs and cat toxins, such as acetaminophen, can lead to swollen legs or paws through liver damage, inflamed blood vessels, or other processes.

• Allergic reactions and autoimmune diseases can make blood vessels leaky and lead to swollen legs or paws.

When just one or maybe two legs or paws are swollen, your cat is probably experiencing a localized problem like one of the following:

• Injury: The inflammation, bleeding, or infection associated with wounds, embedded foreign objects, joint sprains, muscle strains, broken bones, hematomas, tendonitis, and dislocated joints can all cause swelling in a cat’s legs or paws.

• Arthritis: The inflammation associated with arthritis can lead to the overproduction of joint fluid, and bony growths that make joints appear larger than normal.

• Abscess: When cats fight, bite wounds often become infected and form an abscess. These swellings can become quite large and painful.

• Injection reaction: Cats often receive vaccines and other injections low on their legs. It’s not unusual for a small swelling to appear at the injection site.

• Snake bites and insect bites or stings: Stings and bites often create inflammation that makes blood vessels leaky, and they may also become infected. Both of these can lead to tissue swelling.

• Obstruction (blockage) of the veins or lymphatic system: Anything that presses on a vein or lymphatic channel, like a tumor or rubber band around a leg, increases pressure within the vessel, causing it to leak fluid.

• Tumor: Benign or malignant tumors affecting a cat’s legs or paws can create visible swelling and may become inflamed, infected, or put pressure on nearby vessels.

When a cat’s legs look fine and just their paw pads or toes are involved, it’s important to consider the following:

• Plasma cell pododermatitis: Also called pillow foot, plasma cell pododermatitis is an immune-mediated disease that can make a cat’s foot pads (often more than one) become swollen and sometimes discolored or ulcerated (having an open sore).

• Calicivirus infection: Ulcers are common when a cat is infected with calicivirus, and they can involve a cat’s paws and paw pads. They may become swollen, particularly if a secondary bacterial infection develops.

• Eosinophilic granuloma complex: The raised, often pink areas of skin that can come with eosinophilic granuloma complex (an inflammatory disease) usually involve a cat’s lips, thighs, or belly, but the foot pads can also be affected.

• Lung-digit syndrome: Carcinoma of the lung (a type of cancer) can spread to a cat’s toes, making them appear swollen.

How Do Vets Diagnose Swollen Cat Paws and Legs?

Cats with swollen paws and legs often need to be seen by a veterinarian. The doctor will start by asking questions such as:

• How long the swelling has been present?

• How long did it take to develop?

• Has the swelling changed over time?

• Have you seen any other symptoms?

Next, they will perform a thorough physical exam to look for clues as to what might be going on.

Unless the problem is obvious (an abscess, for example), the vet may also need to run some diagnostic tests, which could include a complete blood cell count, a blood chemistry panel, a urinalysis, tests for common infectious diseases like feline leukemia and feline immunodeficiency virus, x-rays, or tissue biopsies.

How Vets Treat Swollen Legs and Paws in Cats

Treatment for swollen legs and paws in cats will vary, based on the underlying problem, but some common types of therapy include:

• Antimicrobials (antibiotics for bacterial infections, for example)

• Doxycycline, corticosteroids, or other medications that calm the immune system for diseases like plasma cell pododermatitis or eosinophilic granuloma complex

• Pain relief

• Diuretics to help move fluid out of tissues

• Surgery to drain abscesses, repair injuries, or remove tumors

• Supportive care

Working together, you and your veterinarian can figure out the best way to treat your cat’s swollen legs or paws so those fuzzy feet can quickly get back into action.

Featured image: iStock.com/VYCHEGZHANINA