Sarcoptic Mange (Dog Scabies): Signs, Treatment and Human Risk

If your dog suddenly can't stop scratching, and the skin on its ears and elbows looks crusty, scabies should be on your list. It's one of the itchiest skin diseases a dog can get. It's also one of the few that can spread to you.

The good news is that sarcoptic mange responds well to modern medicines. The catch is that it has to be caught, confirmed and treated across the whole household. This guide covers what to look for, how it spreads and what happens at the vet.

What is sarcoptic mange?

Sarcoptic mange is a skin disease caused by the mite Sarcoptes scabiei (variety canis in dogs). People know it as scabies. The female mite tunnels into the upper layer of skin and lays eggs. The eggs hatch into larvae, grow into adults and mate, all within about 17 to 21 days.

The itch isn't from the bite itself. It's an allergic reaction to the mites and their droppings. That's why a small number of mites can drive a dog frantic. It's a bit like a sand-flea bite on a beach holiday, but multiplied across the whole body and lasting for weeks.

Don't confuse it with the other common type. Demodectic mange is caused by a different mite that lives in the hair follicles, isn't contagious and is usually much less itchy. Our overview of mange in dogs compares the two side by side.

Signs of sarcoptic mange

The first sign is almost always itching, and it tends to come on suddenly and badly. Dogs scratch, chew, rub on carpets and lose sleep. Other signs build as the skin reacts.

Early signs

In the first weeks you may notice small red bumps, pink skin and fine scabs. The itch is typically worst on the hairless or thinly haired parts of the body. The most common sites are the ear edges, elbows, hocks (ankles) and the belly and chest.

Many owners first notice crusty, scabby ear tips. This is the "canine scabies ears" pattern, and it's a strong clue. Vets often rub the ear margin between finger and thumb. A dog with scabies commonly responds with a reflex scratching kick of the back leg.

Advanced signs

Without treatment, the mites spread across the belly, chest, legs and face. Signs then include:

• Thick yellow or gray crusts
• Hair loss, especially on the legs and belly
• Thickened, dark, leathery skin
• Skin infections (bacterial or yeast)
• Weight loss, poor appetite and low energy

Severe cases can leave a dog depressed and thin. Puppies, senior dogs and sick dogs are hit hardest.

Carrier dogs and hidden cases

Some dogs carry a few mites with little or no itching. They look healthy, but they can still pass the mites to others. That's one reason a household outbreak can seem to come from nowhere. A thick-coated dog may also hide early crusts under its fur, so the first thing you notice may simply be night-time scratching and a restless dog.

Scabies or allergies?

It's an easy mistake. Flea and food allergies also cause itchy skin. The differences are timing and pattern. Allergies tend to be seasonal, slow to build and focused on the paws, face and ears. Scabies tends to be explosive, with severe itching within weeks, often in a dog that has just been boarded, groomed or exposed to other dogs.

How dogs catch scabies

Sarcoptic mites spread through direct contact with an infested dog. They can also survive off the host for a short time, so bedding, brushes and kennels can pass them along.

Common sources

• Dog parks, daycare and boarding kennels
• Groomers that don't clean tables and tools between dogs
• Shelters and rescue facilities
• Foxes and other wildlife that visit the yard or walking trails
• A new puppy or rescue dog that hasn't been checked

Signs usually appear 10 days to 8 weeks after exposure. So the source may be well in the past by the time your dog starts scratching. A dog that was at the kennel six weeks ago can still be the culprit.

Can cats and other pets catch it?

Other dogs in the house are at the highest risk. Cats and other pets can be affected as well, though less often. Vets typically recommend treating every pet in contact with the infested dog. The Cornell guidance is clear that all dogs in the household should be treated, even those not showing signs.

Diagnosing sarcoptic mange

Diagnosis is a mix of detective work and testing.

History and exam

Your vet will ask when the itching started, whether other pets or people are itchy and where your dog has been. They'll check the ears, elbows, belly and hocks and may try the ear-margin reflex test.

Skin scrapings

Scraping the skin and looking at the sample under a microscope is the standard test. The problem is that scabies mites are hard to find. A dog with severe itching may only have a few mites, and they bury deep. A negative scraping doesn't rule scabies out. Vets often take several scrapings from different places to improve the odds.

Treating on suspicion

When the signs fit, the test is negative and other causes have been ruled out, many vets start treatment anyway. If the itch settles on a scabicide, that confirms the diagnosis. Blood tests for mite antibodies and skin biopsies are also available, though used less often.

Dog scabies treatment

The old treatments were smelly dips and weekly baths. Today, most dogs are treated with spot-on or oral medicines.

Your vet picks the product based on your dog's breed, age and health. Many dogs need a combination of treatments, and some need extra medicine for the skin. Antibiotics clear secondary infections. Short courses of anti-inflammatory medication can ease the itch while the mites die off.

Medicine safety

Never use a product made for another species or another dog without asking. Some herding breeds, including Collies, Shetland Sheepdogs and Australian Shepherds, can carry the MDR1 gene change that makes ivermectin and related drugs dangerous at some doses. Puppies under a certain age or weight can't use some products. Tell your vet your dog's breed and age, and any other medicines it takes. Flea products made for cats can be toxic to dogs, so read labels carefully.

Treat the whole household

Every dog in the home should be treated, even if some look fine. Mites on a symptom-free dog will reinfect the others. Ask your vet about cats too.

Cleaning the environment

Mites don't live long away from a host, so you don't need to fumigate the house. Do these things instead:

• Wash bedding, blankets and soft toys in hot water, or replace old bedding
• Wash collars, harnesses and leashes
• Vacuum floors, sofas and the car
• Wipe hard surfaces such as crates and grooming tools

VCA suggests washing bedding in a diluted bleach solution (about 1 ounce of bleach to a gallon of water) or discarding it. Check what's safe for the fabric.

What to expect during recovery

Most dogs feel noticeably better within about two weeks. Full healing takes around 6 to 8 weeks. During that time, crusts loosen and fall away, the skin darkens or flakes a little, and hair starts to grow back.

Call your vet if your dog is still scratching hard 4 to 5 days after treatment, if new sores appear, or if a family member is still itchy after two weeks. Don't stop medicine early because the scratching has eased. The mites may still be alive.

The itch is the hardest part. A soft cone or a loose t-shirt can stop a dog from scratching raw skin, and a cool, damp cloth on sore spots can offer brief relief. Ask your vet before using any shampoo, because some strip the skin and make it worse. Keep nails short, because scratching with long nails turns irritated skin into open wounds.

Keep your dog away from other dogs until the vet clears it. That includes the dog park, daycare and grooming appointments.

Protecting your family

Scabies from a dog is a nuisance rather than a danger for most people. Wash your hands after handling your dog. Don't let it sleep in your bed until it's been treated. Keep young children and anyone with a weakened immune system from close contact. If you develop an itchy rash, see your doctor. Human scabies treatment is different from dog treatment, so never use your dog's medicine on yourself.

Scabies in puppies and older dogs

Puppies and seniors often struggle more. A puppy has less body weight to carry mites and medicine, and some products aren't approved under a certain age or size, so your vet may choose a gentler option. Older dogs may have other illnesses that slow healing. Both groups can lose weight quickly if they're too itchy to eat or sleep, so weigh them weekly and tell your vet if they're slipping.

Preventing scabies

There's no vaccine. The best protection is to limit exposure and keep dogs healthy.

• Avoid contact with dogs that are itchy, crusty or bald
• Keep your dog away from foxes and other wildlife
• Pick groomers and kennels that disinfect between dogs
• Ask your vet whether your flea and tick preventive also covers sarcoptic mites
• Check new dogs and rescues before they meet your pets

When to see a vet

See a vet as soon as you notice sudden, intense itching, crusts on the ear tips or elbows, or unexplained hair loss. Early treatment is easier, cheaper and safer for your family.

Go the same day if your dog has:

• Raw, bleeding or pus-filled skin
• Weight loss, fever or lethargy
• Itching that prevents sleep or eating

If your dog is itchy but has patchy bald areas and little scratching, especially if it's young, mange in puppies may be the answer. For other causes of red, sore skin, see hot spots on dogs and our skin and coat hub.