Warts on Dogs: What They Look Like and When to Worry

How to tell puppy mouth warts from older-dog growths, which bumps need a needle sample, and when a bleeding or growing wart needs a vet today.

Quick answer: Wart-like bumps on dogs are often benign. Young dogs get viral papillomas in and around the mouth, which VCA Animal Hospitals says usually clear within 2 to 3 months. Older dogs often grow benign oil-gland bumps, but a new wart-like growth on an adult dog needs an in-person exam within days, the same day if it bleeds or grows fast. Only a needle sample or biopsy can tell for sure.

This article is general information, not a diagnosis. If you think your pet is in danger, go to the nearest emergency animal hospital.

What do dog warts look like?

Most dog warts are small, raised bumps with a hard, cauliflower-like surface on the lips, mouth, eyelids, feet or body, and in older dogs many wart-like bumps are actually benign oil-gland growths, so a vet should look at any new one. The Merck Veterinary Manual says multiple warts are generally seen in younger dogs, while single warts are more frequent in older dogs and may not be caused by a virus. VCA Animal Hospitals says viral papillomas are most common on the feet and around or in the mouth.

Note where the bump is, its surface, its color, how many there are, and whether it moves with the skin or feels fixed; color alone tells you little. Rule out an engorged tick, and on the belly, a nipple. Merck says skin warts are common in Cocker Spaniels and Kerry Blue Terriers.

When is a wart or bump on a dog an emergency?

A wart or bump on a dog needs an emergency vet now if blood is still flowing freely after several minutes of steady pressure, if a mouth growth makes breathing or swallowing hard, or if an eyelid bump comes with an eye that looks cloudy, hazy or bluish, bulges, or stays shut. Any puppy that is weak, wobbly, trembling, cold or hard to wake also needs an emergency vet now. A dog or cat that licked or ate a human wart, acne or callus remover needs an emergency vet now if it vomits, seems weak or acts off, and otherwise a call to a pet poison line now (numbers below).

Go in person the same day for a bump that bled (even if it stopped), grows fast, or is ulcerated, oozing, smelly or spreading, and for an eyelid bump with squinting, pawing at the eye, discharge, tearing or redness.

Puppy mouth warts: what canine papillomavirus does

Young dogs often get clusters of papillomas in and around the mouth from canine papillomavirus, and VCA Animal Hospitals says these puppy mouth warts usually clear up within 2 to 3 months. Have a vet look at the first ones, then follow that vet's plan. The Merck Veterinary Manual says they often go away on their own when there are only a few and they do not get in the way of eating, but dogs may bite larger ones while chewing, so they bleed and get infected.

• Trouble breathing or swallowing: an emergency vet now.
• Warts that make picking up food or chewing hard: an in-person vet within days.
• A wart that bleeds or looks infected: a vet the same day.
• Warts that have not cleared by about 3 months: an in-person recheck.

RexVet's guide to a new puppy's first week gives the eating rule: a puppy under 4 months that has eaten nothing for more than 8 hours needs to be seen in person today (an emergency vet if your clinic can't), and a toy-breed puppy that skips a meal needs a call to the vet now.

Why does my old dog keep getting warts?

Older dogs commonly grow benign wart-like oil-gland bumps called sebaceous adenomas and sebaceous hyperplasia, which the Merck Veterinary Manual says appear most often on the head, but any new wart-like growth on an older dog still needs an in-person exam within days. Merck says hyperplasia lumps seldom grow past 1 cm and show up mostly on the head and belly, and that adenomas are often multiple.

Merck also says squamous cell carcinoma, a skin cancer of older dogs, can grow outward with a surface like a wart, and that viral warts infrequently progress to it. Many papillomas in an older adult dog should raise suspicion of an immune problem, for example lymphoma, Merck adds.

From RexVet's own visit data, across all visit reasons: 41% of RexVet video visits were for pets aged 7 or older.

Is it a wart or a tumor on my dog?

You cannot tell a dog wart from a tumor by looking: veterinary oncologist Dr. Sue Ettinger's See Something, Do Something campaign says any lump pea-sized (about 1 cm) or larger that has been there a month needs a needle sample, with a biopsy if that gives no answer. Dr. Ettinger writes in Today's Veterinary Practice that even an experienced cancer specialist cannot look at or feel a mass and know what it is. That rule is an outer limit, not a waiting period.

RexVet's guide to a sore or bump a dog keeps licking gives a sooner deadline: "A firm or raised lump, a sore sitting on a lump, or a spot that grows or swells and shrinks needs an in-person needle test within days, or the same day if it bleeds or grows fast." Never squeeze a bump that swells and shrinks, since it can be a mast cell tumor; RexVet's page on skin bumps in pit bulls gives the same advice and says a lump plus vomiting, black tarry stool or not eating needs an in-person vet the same day, and that vomiting blood, pale gums or weakness mean an emergency vet now.

Color does not settle it: the Merck Veterinary Manual says malignant melanomas may or may not be dark and are most common on the lips, in the mouth and in the nail beds; in a nail bed, one can show as a swollen toe or a lost nail. A growth at a nail with a limp, a swollen toe, or a misshapen or lost nail on an adult dog needs an in-person exam within days. An adult dog with a mouth growth plus drooling, loose teeth or bad breath needs a vet within days. In the table, "Can't tell" means only a needle sample or a biopsy can say.

Bump	Could be	Next step
Cauliflower bumps in a young dog's mouth	Viral wart	Vet look, then plan
Mouth warts make eating hard	Viral wart	In person, within days
Young dog's warts not gone by 3 months	Viral wart	In-person recheck
New wart-like bump on an adult dog	Can't tell	Exam within days
Many new warts on an older dog	Immune issue	Exam within days
Pea-sized or bigger, there a month	Can't tell	Needle sample
Firm, fixed or raised lump	Can't tell	Needle sample within days
Swells and shrinks	Mast cell tumor	Needle sample within days; never squeeze
Adult dog: lip, mouth or nail bed	Can't tell	Exam within days
Dark or black bump	Can't tell	Exam within days
Eyelid bump, eye comfortable	Gland growth	Exam within days
Eyelid bump plus squinting	Eye pain	Same day
Grows fast, bleeds, oozes or smells	Can't tell	Same day
Still bleeding after several minutes of pressure	Bleeding	Emergency vet now
Bump a clinic already sampled	Diagnosed	Photos, recheck

What about a wart on a dog's eyelid?

A wart-like bump on a dog's eyelid needs an in-person vet within days if the eye is comfortable and open, the same day if the bump grows fast or the dog squints, paws at the eye, or has discharge, tearing or redness, and an emergency vet now if the eye looks cloudy, hazy or bluish, bulges, or stays shut. The Merck Veterinary Manual says meibomian gland adenomas and adenocarcinomas make up about 60% of eyelid tumors in older dogs, that papillomas are also a frequent eyelid tumor, and that mouth papillomas in young dogs can involve the eyelids. RexVet's guide to a dog squinting one eye covers the eye signs.

My dog's wart is bleeding: what now?

If a dog's wart is bleeding, press a clean cloth on it with steady pressure; if blood is still flowing freely after several minutes, go to an emergency vet now, and if it stops, have it seen in person the same day. Hold the pressure without lifting to check, keep your dog from licking or chewing the spot, and put no human creams or wart products on it. A wart that oozes pus, smells or keeps reopening also needs a vet the same day.

Can I remove a dog wart at home?

You should never cut, tie off, burn or freeze a dog's wart at home, and never put a human wart, acne or callus remover on it, because Pet Poison Helpline lists those medicines among products that can contain aspirin-like compounds that poison dogs and cats. Home removal can cause bleeding or infection, and a vet decides whether and when a wart comes off; skip internet home remedies too.

Pet Poison Helpline says cats are much more sensitive to aspirin poisoning than dogs. If a pet licked or ate one of these products, go to an emergency vet now if it vomits, seems weak or acts off. Otherwise, call ASPCA Animal Poison Control at (888) 426-4435 (a consultation fee may apply) or Pet Poison Helpline at (855) 764-7661 (a per-incident fee applies) now.

Are dog warts contagious?

VCA Animal Hospitals says dog papilloma warts spread between dogs through direct contact and through an infected dog's toys, food bowls or bedding, but the virus is species-specific, so dog warts do not spread to people or cats. VCA advises keeping an affected dog away from other dogs until the warts are gone, so skip daycare and dog parks. The Merck Veterinary Manual says isolation helps only partly, because many dogs are exposed before anyone notices a wart; warts can take weeks to several months to appear after exposure.

How to get rid of dog warts: what a vet does

A vet diagnoses a dog wart by examining it and, when needed, taking a needle sample or a biopsy, and removes it for diagnosis or when it bleeds, gets infected, does not go away, or (with many mouth warts) gets in the way of eating. The Merck Veterinary Manual says a firm diagnosis of a skin growth generally needs a biopsy, and VCA Animal Hospitals says a needle sample rarely helps with mouth warts. Merck says surgery for benign oil-gland growths is optional unless they are inflamed or infected, and that removing warts early in their growth may lead to recurrence, so the vet picks the timing.

How to track a bump on your dog

To track a bump on a dog, photograph it each month, or sooner if it changes, next to a ruler or coin in the same light, and write down the date, where it is and its size in centimeters. With several bumps, sketch a simple body map and number each one. Note whether a bump feels soft or firm, and any bleeding, licking or color change. Tracking gives your vet a record; it never replaces the exams above.

When a video visit helps, and when it does not

RexVet, a nonprofit online vet service, serves pets located in Florida, New York and Virginia by video visit. A $64.99 live video visit with a licensed RexVet vet, a veterinarian licensed in your pet's state, can be a first look for a dog with a small bump that is otherwise well: a young dog with typical mouth warts that is eating and drinking normally, a new bump on an older dog (to help plan the in-person exam it still needs within days), or a bump a clinic has already diagnosed that you want rechecked against dated photos. The visit helps decide how soon an in-person exam is needed; it never replaces one.

Your dog must be located in Florida, New York or Virginia during the visit. Live video slots run about 8 AM to 11 PM ET. There are no overnight visits, and holiday hours are not confirmed, so check open slots when you book. Book a live video visit.

On camera, the veterinarian can look at the bump and your dated ruler photos, ask how fast it changed, say whether it looks like typical young-dog mouth warts, and tell you how urgent it looks and how soon it needs an in-person needle sample or biopsy. No vet can tell on camera whether a bump is cancer; sampling, removal and eye stain tests need a clinic.

A video visit does not fit every bump. Emergency vet now: blood still flowing freely after several minutes of steady pressure, a mouth mass with trouble breathing or swallowing, or a cloudy, bulging or shut eye. In person the same day: a bump that bleeds or grows fast, a sore that oozes or smells, or an eyelid bump with squinting. In person within days: a firm, fixed or raised lump, a dark bump, a bump at a toe or nail bed, many new warts on an older dog, or mouth warts that make eating hard.

From RexVet's own visit data: Skin trouble was the top reason pet owners booked a RexVet video visit: 27% of visits named skin problems, itching, allergies or hair loss. That finding is about skin concerns in general, not warts.

No prescription is promised. Many warts in young dogs go away on their own, and the veterinarian decides whether any treatment is appropriate. RexVet is not a pharmacy; a pharmacy transfer fee applies when a prescription is sent to an outside pharmacy.

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Frequently Asked Questions

Do dog warts go away on their own?

Often, in young dogs: VCA Animal Hospitals says puppy mouth warts usually clear up within 2 to 3 months. Adult dogs are different: the Merck Veterinary Manual says single warts in older dogs may not be caused by a virus, so a new wart-like growth on an adult dog needs an in-person exam within days. A young dog's warts that last past about 3 months need an in-person recheck.

Can I cut off my dog's wart at home?

No: never cut, clip, tie off, burn or freeze a dog's wart at home. It can bleed or get infected, and only a needle sample or a biopsy shows what it is. Never use a human wart, acne or callus remover on a dog; if a dog or cat licked or ate one, go to an emergency vet now if it vomits, seems weak or acts off, and otherwise call ASPCA Animal Poison Control at (888) 426-4435 (a consultation fee may apply) or Pet Poison Helpline at (855) 764-7661 (a per-incident fee applies) now. Cats are much more sensitive than dogs.

Are mouth warts in my puppy an emergency?

Usually not, but trouble breathing or swallowing, or mouth bleeding that will not stop with pressure, means an emergency vet now. A bleeding or infected wart needs a vet the same day, and warts that make picking up food or chewing hard need an in-person vet within days. A puppy under 4 months that has eaten nothing for more than 8 hours needs to be seen in person today, a toy-breed puppy that skips a meal needs a call to the vet now, and any puppy that is weak, wobbly, trembling, cold or hard to wake needs an emergency vet now.

Is a black wart on my dog cancer?

It can be, so a dark or black bump needs an in-person exam within days, the same day if it bleeds or grows fast. The Merck Veterinary Manual says malignant melanomas may or may not be dark and can look gray or pink in the mouth, so pink does not mean safe either. Only a needle sample or a biopsy can tell.

Can an online vet tell if a bump on my dog is cancer?

No: no vet can tell if a bump is cancer by looking, on camera or in person; that takes a needle sample or a biopsy. Dr. Sue Ettinger's See Something, Do Something campaign says any lump pea-sized (about 1 cm) or larger that has been there a month needs a needle sample. A video visit can help you decide how soon to get that test done in person.

Can an online vet look at a bump on my dog in Florida, New York or Virginia?

Partly: a vet can look at the bump on camera and say how urgent it is, but tests and removal need a clinic. If your dog is located in Florida, New York or Virginia during the visit, a veterinarian licensed in your pet's state can review the bump and your photos and say how soon it needs an in-person test. No prescription is promised. In Florida, a video-only prescription is limited to FDA-approved animal drugs used as labeled, for up to 14 days (1 month for products labeled only for flea and tick control), with no renewal without an in-person exam; human-labeled, controlled and compounded anti-infective drugs need an in-person exam first. Federal rules (21 CFR 530.3) require an in-person exam before off-label or human-drug use in every state. Virginia allows an electronic exam, but that does not override the federal rule, and New York's rules for video-only prescriptions are still unsettled.