Concerned about odd bumps nestled between your dog's toes? It's natural to feel uneasy when discovering something unusual on your pet. Hold off on the panic button, though. You've landed on an all-inclusive guide to interdigital cysts in dogs. By the close of this article, you'll grasp the what, why, and how-to of these cysts. Our aim? To empower you with the insight and assurance needed to properly address this health concern, safeguarding your four-legged companion's comfort and overall wellness.

What are Interdigital Cysts?

First things first: What in the world is an interdigital cyst?

Essentially, it's a small, inflamed lump that can appear between your dog's toes. Imagine a painful pimple; that's somewhat close to what these cysts are. It might look red, feel tender to the touch, or even ooze a bit.

In the vet world, we also call these interdigital cysts in dogs follicular pododermatitis or podofurunculosis.

The Anatomy of a Dog's Paw

Ever given your pup's paws more than a casual glance while belly rubbing? A dog's paw is a marvel of nature, designed for running, digging, and sometimes getting into trouble.

The space between toes is where an interdigital cyst is likely to show up. Understanding the basic anatomy can help you spot issues early on.

Interdigital cysts in dogs are most commonly found on the front paws and most commonly affect the spaces between 3rd and 4th digits or toes.

Different Types of Interdigital Cysts

Okay, so not all cysts are made equal. There are various types that could be affecting your dog.

You've got furunculosis, which usually occurs from bacterial infections at the level of the hair follicle. Follicular cysts are another variety, also linked to hair follicles in the paw.

Interdigital cysts in dogs
interdigital cysts in dogs

Causes of Interdigital Cysts in Dogs

Ever wonder how those specific "follicular" interdigital cysts form on your dog's paws? Think of it like this: Sometimes, a minor injury or constant friction can irritate the skin on the paws that are covered with hair. This irritation triggers something called "follicular hyperkeratosis," which is a fancy way to say the skin around the hair follicles gets thick and dilated.

Here's where it gets interesting. These thickened follicles can get "plugged" or blocked. And when they do, they stretch out and turn into what we know as cysts. The trouble really starts when these cysts burst. Ouch! That not only creates more irritation but also opens the door for nasty bacteria to come in and make things worse.

Most of the time, these cysts start on the part of the paw your dog walks on—the palmar or plantar surface. But as they evolve, they tend to migrate upwards between the toes to what's known as the "dorsal interdigital surface." Yep, you'll often find them hanging out there eventually.

With that, here are the most common causes and contributing factors of interdigital cysts in dogs:

The Hair Factor

Firstly, let's talk hair. Dogs with shorter, coarser hair coats are more prone to interdigital cysts. Breeds like English Bulldogs, Bullmastiffs, Great Danes, and Boxers often find themselves in this boat. Their hair follicles are more susceptible to irritation and rupture.

It's All in the Paws

Next, take a good look at your pup's paws. Breeds with wider paws and more space between the toe pads—think Labradors, German Shepherds, English bulldogs and Pekingese—tend to bear weight on the hairy skin between their pads. This adds extra stress, making interdigital cysts more likely.

Weight Issues

Weight plays a role too. Overweight dogs or those with irregular weight distribution due to lameness can put additional pressure on the spaces between the toes, setting the stage for interdigital cyst formation.

The Lick and Scratch Cycle

You know how your dog can't stop licking or scratching sometimes? Well, this behaviour can damage hair follicles, progressing to cysts. Often, underlying skin conditions like allergic dermatitis contribute to this cycle.

Rough Living

Environmental factors matter as well. Walking on rough surfaces or spending time in cages with hard flooring can traumatize the hair follicles on your dog's paws.

Underlying Conditions

Keep an eye out for secondary bacterial or yeast infections. They often accompany these cysts. Systemic conditions, such as hypothyroidism and Cushing's Disease, can make your dog more susceptible to such infections.

Other Causes

Finally, don't rule out other possibilities like foreign objects, demodex skin mites, or even certain types of tumours as potential causes for cyst-type lesions.

Spotting the Symptoms: Early Signs and When to See Your Vet

Early detection can make all the difference when dealing with interdigital cysts in dogs, so it's crucial to know the signs that warrant a vet visit.

Licking and Chewing

Is your dog constantly licking or nibbling at their paws? That's often a sign something's irritating them. Excessive licking can worsen interdigital cysts.

Redness and Swelling

Look out for red, swollen skin between your dog's toes. Interdigital cysts in dogs are known to create inflammation and with that, redness and swelling can ensue.

Limping

Notice a slight limp? Pain from the cyst can cause irregular walking patterns. If it persists, it's a clear sign to consult your vet for advice.

Discharge

A yellow or green discharge is a red flag. It usually indicates severe infection and requires immediate veterinary attention.

Odor

Bad smells emanating from the paw area can be due to infection, especially secondary fungal infections. Please don't ignore it.

Diagnostic Steps

Identifying the underlying cause of interdigital cysts can be a complicated process due to various factors that contribute to it. Therefore, what should you anticipate when you take your furry companion to the veterinarian?

  • Initial Assessment: First up is the history and examination. Your vet will observe your dog's overall health, and walking pattern, and ask you questions about their living conditions. If they notice a single draining tract, they might investigate foreign bodies like plant material or wood splinters.
  • Microscopic Analysis: Next is skin cytology. Your vet will take a small sample from the cyst to check for bacterial infections, yeast overgrowth, inflammation, or abnormal cells.
  • Skin Tests: In some cases, a skin scrape or a hair pluck test may be done to check for Demodex mites, a microscopic parasite that can contribute to interdigital cysts.
  • Diet Check: If your dog has had ongoing issues with itching and it does not appear to be related to season, an elimination diet trial may be in order to rule out food-related skin reactions.
  • Blood Work: Endocrine disorders like hypothyroidism can also be a factor. Blood tests will rule this out if your dog shows clinical signs of these conditions.

Treatment Options

Managing interdigital cysts involves both addressing the immediate symptoms and mitigating underlying causes to prevent future flare-ups.

Address Predisposing Factors

First things first, tackle any contributing conditions like atopic dermatitis. Effective management of such conditions can reduce self-inflicted trauma, thus minimizing the risk of cyst recurrence.

Medication Options

  • Antibiotics: Crucial for treating secondary bacterial infections. Often a prolonged course is needed, carefully chosen based on culture and sensitivity tests.
  • Corticosteroids: Effective for severe and deep inflammation.
  • Cyclosporine: Beneficial for underlying atopic dermatitis.
  • Topical Glucocorticoids: Good for superficial localized issues or when systemic or oral options are not suitable.
  • Apoquel and Cytopoint: Useful for allergies but less effective for the deep inflammation associated with interdigital cysts.

Protective Footwear

Investing in doggy boots can offer a preventive layer, especially for dogs exposed to abrasive terrains or who spend time in cages.

Skin Barrier Enhancements

Supplements like essential fatty acids could provide additional relief by strengthening the skin barrier. Ask your veterinarian for recommendations on products they carry and recommend.

CO2 Surgical Laser Treatment

A promising option, CO2 laser surgery ablation has successfully prevented recurrence in a significant number of cases according to studies.


In conclusion, interdigital cysts in dogs are a complex health issue with various contributing factors, including the breed, weight, and environmental conditions of the dog, as well as underlying health conditions.

Symptoms to watch out for include excessive licking or chewing of the paws, redness and swelling, a noticeable limp, discharge, or a bad odour from the paw area. Treatment options range from addressing predisposing factors and prescribing specific medications to investing in protective footwear and enhancing the skin barrier.

Thanks for reading and as always, if you have any questions or concerns regarding the health of your dog, please contact your veterinarian.