A red, swollen bump between your dog’s toes can be easy to dismiss as a minor irritation. But when your dog keeps licking its paws, chewing at the area, or starts limping, the problem may be more than a simple skin bump. An interdigital cyst in dogs, more accurately described in many cases as an interdigital furuncle, is an inflammatory lesion that develops in the webbing between the toes and can become painful or infected.
These lesions can look similar to other causes of a cyst on a dog paw, so appearance alone may not tell you what is causing the problem. Understanding what to watch for can help you recognize when a persistently irritated dog paw needs veterinary attention. Let's get started.
What Is an Interdigital Cyst in Dogs?
Interdigital cyst is a common term pet owners use for bumps that form between a dog’s toes. However, many of these lesions are not true cysts. They are often interdigital furuncles, which are areas of deeper inflammation involving hair follicles and surrounding tissue. In some cases, the lesion can rupture and release fluid.
The area may begin with mild redness or a small bump before becoming larger and more irritated. Because the webbing between the toes is exposed to friction and moisture during normal activity, irritation in this location can continue once the inflammatory process starts.
What Does a Dog Interdigital Cyst Look Like?
Just like how every dog is unique, these lesions can also look different from one dog to another. When checking your dog’s paw, you may notice:
- A round, raised bump between the toes
- Red or reddish-purple skin around the affected area
- Swelling or a shiny appearance to the skin
- A small opening in the skin
- Fluid or other drainage from the lesion
- Hair loss around the bump
- Thickened or crusted skin
- More than one bump, particularly with recurring or extensive problems
Why Does a Red Bump Develop Between a Dog’s Toes?
There is not always one single cause. Interdigital lesions can develop after trauma or irritation to the hair follicles in the webbing. Hair shafts can become forced into the skin, where they trigger inflammation. Bacterial infection may then develop or occur alongside that inflammation.
Some dogs are more prone to these problems because of paw shape, hair characteristics, or repeated pressure on the spaces between the toes. Recurrent lesions can also be associated with underlying skin disease, including allergic dermatitis. Excessive licking can also add another layer of irritation.
Signs Your Dog May Have an Interdigital Cyst
Your dog cannot tell you when something is wrong, so it's important to notice subtle changes in their behavior. Because these lesions can be itchy or painful, changes in your dog’s routine or demeanor may be just as useful to notice as the appearance of the paw.
Watch for changes that persist, worsen, or interfere with normal walking. Common signs can include:
- Frequent licking or chewing of the paws
- Redness or swelling between the toes
- A raised bump or nodule in the webbing
- Warmth, irritation, or tenderness around the lesion
- Hair loss around the affected area
- Fluid, blood, or discharge from an opening in the skin
- Limping or reluctance to put weight on the affected foot
A dog that repeatedly focuses on one paw may be reacting to discomfort even when the bump itself looks relatively small. It is also possible for the visible lesion to look worse after the hair around the paw is clipped or when the skin is closely examined.
Other Causes of a Bump Between Your Dog’s Toes
Not every red bump is an interdigital furuncle. A foreign object, such as plant material, can become embedded in the paw and create localized inflammation. Allergies and other skin conditions can also cause redness, licking, irritation, and changes to the skin between the toes.
Other possibilities include bacterial or fungal infections, follicular cysts or comedones, traumatic injuries, and less common skin disorders. Because these conditions can overlap in appearance, trying to identify the cause based only on a photograph or by squeezing the bump at home may be misleading.
Why the Cause Matters
When an interdigital lesion keeps returning, there may be an underlying reason that needs attention. Allergic skin disease, parasites, repeated trauma, or a foreign body can contribute to ongoing inflammation. Treating only the visible bump without addressing the contributing factor may allow the problem to come back.
When Should a Veterinarian Examine a Cyst on a Dog Paw?
A small irritated spot may not seem urgent, but a persistent or painful bump deserves a closer look, especially when your dog is licking paws repeatedly or developing a limp. A veterinary examination can help distinguish an interdigital furuncle from a foreign body, infection, allergy-related lesion, or another skin problem.
Depending on the appearance and history, a veterinarian may examine cells or material from the lesion, evaluate for parasites, perform bacterial testing, or recommend additional diagnostic work when a lesion is unusual or recurrent. Some solitary lesions require exploration to look for a foreign object, while recurring or atypical lesions may need further testing to determine what is driving the problem.
It is also important to avoid repeatedly squeezing, puncturing, or applying medications intended for people unless your veterinarian has advised you to do so. The appropriate treatment depends on what is causing the lesion and whether infection, inflammation, or another condition is present.
What Can You Do If Your Dog Has a Red Bump Between the Toes?
Start by taking a close look at the paw and noting whether the area is becoming larger, draining, or affecting your dog’s walking. You can also keep track of how often your dog licks or chews the foot and whether similar bumps are appearing on other paws.
Most importantly, a bump that does not resolve, keeps returning, becomes painful, or causes limping should not simply be ignored. Getting the underlying cause identified gives your veterinarian a clearer path for treatment and helps determine whether the problem is an isolated lesion or part of a broader skin issue.
If you have questions, we would love to answer them for you. Please give us a call at the office at (603) 287-1181, or you can email us at [email protected]. Our staff would love to talk with you!
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