Interdigital Cysts in Dogs

If you’ve noticed a red, swollen bump between your dog’s toes, it may be an interdigital cyst. These lumps can be painful and may burst and ooze. Despite the name, most aren’t true cysts. They’re usually deep infections or inflammation of the hair follicles, called interdigital furuncles. The good news is they’re treatable, and finding the cause helps stop them coming back.

What is an interdigital cyst?

An interdigital cyst is a lump that forms in the webbing between a dog’s toes. It’s often:

• Red or purple
• Raised and shiny
• Filled with blood or pus
• Painful to the touch

It may burst, drain and then come back.

What causes interdigital cysts?

Short, bristly hairs

In short-coated breeds, the stiff hairs between the toes can be pushed backward into the hair follicles when a dog walks. This leads to inflammation and infection.

Breeds at higher risk

• English Bulldogs
• Labrador Retrievers
• Shar-Peis
• Boxers
• Great Danes
• Bull Terriers

Other causes

• Allergies, which cause itchy paws and licking
• Excess weight, which spreads the toes and puts pressure on the webbing
• Foreign objects, like grass seeds
• Mites (demodex)
• Abnormal paw or leg structure
• Bacterial or fungal infections

Our article on spring allergies and why your dog won’t stop scratching explains how allergies can affect the paws.

Signs of an interdigital cyst

• A lump between the toes
• Licking or chewing at the paw
• Limping
• Redness and swelling
• Bleeding or pus from the bump
• Hair loss on the paw

Our article on my dog is limping but still playing explains when a limp needs a vet.

How is it diagnosed?

Your vet will examine the paw and may:

• Take a sample of cells from the lump (cytology)
• Do a skin scraping to look for mites
• Culture the fluid to choose the right antibiotic
• Take X-rays to look for foreign objects
• Investigate allergies if the problem keeps returning

How are interdigital cysts treated?

Treatment depends on the cause and may include:

• Antibiotics or anti-inflammatory medicines prescribed by your vet, sometimes for several weeks
• Soaking the paw in warm water or a medicated solution, as your vet directs
• Medicated wipes or shampoos
• Allergy management
• Weight loss, for overweight dogs
• Surgery or laser treatment for cysts that keep coming back

Don’t try to squeeze or pop the bump at home. This can push infection deeper and cause pain.

How to help prevent them

• Keep paws clean and dry, especially after walks
• Check between toes for grass seeds and debris
• Keep your dog at a healthy weight
• Manage allergies with your vet’s help
• Trim long hair between the toes

When to call a vet

Call your vet if your dog has a lump between the toes, especially if it’s growing, bleeding, painful or making your dog limp. Some cancers can also look like paw bumps, so it’s important to have them checked. Our article on what to do if your dog has a lump explains which lumps need attention.

Frequently asked questions

Will an interdigital cyst go away on its own?

Sometimes it drains and shrinks, but it often comes back without treatment of the cause.

Are interdigital cysts contagious?

No. They don’t spread to other pets or people.

Paw problems? Ask a vet

Talk to a licensed vet 24/7, even on holidays, by chat, voice call or video call. Your first month is free with code FREEMONTH, then US $9.99/month, at NYPTeleVet.com. One membership covers up to 6 pets, and you can cancel anytime.

Our vets can’t prescribe medication, but they’ll tell you what’s likely needed and when an in-person visit is the next step.

Sources

• Interdigital Cysts in Dogs, VCA Animal Hospitals
• Interdigital Cysts on Dogs, PetMD
• Abscesses Between the Toes (Interdigital Furunculosis) in Dogs, Merck Veterinary Manual