Mange in Dogs: Sarcoptic vs. Demodectic Symptoms, Causes & Treatment

You might first notice a small patch of missing fur near your dog's eye. Or perhaps your dog has been scratching their ears for days, and now the skin looks red and crusty.

Both can be signs of mange, but they can also point to other skin conditions. And if you have another dog at home, there's a question worth answering quickly: could they catch it too?

What Causes Mange in Dogs?

Mange happens when parasitic mites infest a dog's skin or naturally occurring mites multiply excessively inside the hair follicles.

One type usually comes from contact with an infected animal, while the other develops when mites already present on a dog's body grow out of control. That difference explains why one dog with mange may need to be kept away from other pets, while another doesn't.

Sarcoptic Mange: The Contagious Type

Sarcoptic mange, also called canine scabies, is caused by Sarcoptes scabiei var. mites that burrow under the skin of dogs.

These mites cause a major allergic reaction. The itching can be hard to ignore, and affected dogs may scratch, bite, or rub against furniture.

The infestation spreads primarily through contact with infected animals, including other dogs, foxes, and coyotes. Shared bedding and contaminated environments can also contribute to transmission. If your dog has sarcoptic mange, other dogs in the household will generally need treatment too, even if they are not scratching yet.

Demodectic Mange: When Normal Skin Mites Overgrow

Demodectic mange works differently. Most dogs naturally carry Demodex mites, which they acquire from their mothers shortly after birth.

Normally, these mites live inside the hair follicles without causing trouble. Problems begin when their numbers increase beyond what the skin can control. This is particularly common in young puppies. A puppy might develop one or two small bald patches, often around the face or front legs.

Adult dogs can develop demodicosis too. When it appears later in life, veterinarians may investigate conditions such as Cushing's disease, diabetes, cancer, or immune suppression associated with long-term steroid treatment.

Unlike sarcoptic mange, canine demodicosis generally isn't contagious through ordinary contact and doesn't pose a recognized zoonotic risk to humans.

What Does Mange Look Like in Dogs?

Mange does not look identical on every dog. Some puppies with localized demodicosis develop small, round areas of hair loss. Dogs with sarcoptic mange may have extensive redness, crusting, and irritated skin. The amount of scratching can provide another clue.

A bald patch that gradually spreads, develops scabs, or starts producing an unpleasant odor may indicate worsening disease or a secondary skin infection.

Mange is not the only reason dogs lose fur, though. Allergies, fleas, bacterial infections, and other conditions can cause similar changes. Our guide to why dogs get itchy and lose hair explains those possibilities in more detail.

Is It Mange, Ringworm, or Something Else?

A bald patch could be mange, but it could also be ringworm. Both can leave your dog's skin red, flaky, and missing fur. The difference is that ringworm comes from a fungus, while mange is caused by mites. 

You can't always tell by the shape of the patch either. Ringworm doesn't necessarily form a ring, and demodectic mange can leave round bald spots too. 

Your vet may need to test the skin to tell them apart. Ringworm and sarcoptic mange can also affect people, but demodectic mange generally doesn't.

Our guide to ringworm in dogs explains its symptoms, spread, and treatment.

What if Your Dog Is Scratching but You Can't Find Fleas?

Your dog may still be scratching even if you haven't spotted a single flea. It could be a reaction to flea bites, something in their food or environment, or a yeast or bacterial skin infection. Mange is another possibility, and sometimes more than one skin problem can be present at the same time.

Our article on why dogs keep scratching without visible fleas explores these possibilities. You can also compare bacterial, fungal, and allergic conditions in Dog Skin Infections 101. If itching continues or hair loss spreads, arrange a veterinary examination rather than trying several treatments at home.

How Does a Vet Confirm Mange?

Your veterinarian will examine the affected skin and may collect a skin scraping to look for mites under a microscope. For demodectic mange, deeper scrapings or hair samples can help identify mites living inside the follicles.

Sarcoptic mange can be harder to confirm. A dog may have severe symptoms even when very few mites are present in the collected sample. A negative scraping does not always rule out scabies.

According to Cornell University College of Veterinary Medicine, veterinarians may recommend a supervised treatment trial when symptoms strongly suggest sarcoptic mange despite negative scraping results. Your vet may also check for secondary bacterial or fungal infections.

How Is Mange in Dogs Treated?

Treatment needs to kill or control the responsible mites. Your veterinarian will select medication based on the type of mange, your dog's age, general health, breed, and the severity of the condition.

Treating Sarcoptic Mange

Sarcoptic mange requires targeted antiparasitic medication. Veterinarians may prescribe suitable treatments containing selamectin, moxidectin, or other effective medicines. Certain isoxazoline flea and tick medications are also used for mange, sometimes off-label in the United States.

Some breeds need additional caution with certain antiparasitic drugs, particularly at higher doses. See the MDR1 medication warning below.

Treatment generally extends beyond the affected dog. Other dogs in the household usually need treatment because they may have been exposed before developing symptoms. Wash bedding, clean shared sleeping areas, and follow your veterinarian’s advice about restricting animal contact.

Treating Demodectic Mange

If your puppy has a mild, localized case, your veterinarian may recommend monitoring rather than immediately prescribing mite-specific medication. Some small patches resolve as a puppy’s immune system matures.

Generalized demodicosis is different. When hair loss covers larger areas or secondary infections develop, antiparasitic medication and follow-up examinations are usually necessary. Veterinarians may use suitable isoxazoline medications, including afoxolaner, fluralaner, sarolaner, or lotilaner. Their use for demodicosis may be off-label in the United States.

Treatment sometimes continues for several months. Adult dogs may need additional investigation for underlying conditions contributing to mite overgrowth. Veterinarians generally advise against breeding dogs with generalized juvenile demodicosis because of concerns about inherited susceptibility.

The Companion Animal Parasite Council’s Demodex guidelines provide further clinical information.

Medication safety reference: Washington State University-MDR1 in Dogs.

What Can You Do at Home While Your Dog Recovers?

Once treatment begins, your dog may start scratching less before the skin looks completely normal. Hair regrowth can take longer, particularly if affected areas were badly inflamed or developed secondary infections. Continue the prescribed schedule even when your dog starts looking better.

Can You Bathe Your Dog During Mange Treatment?

Sometimes, yes. Check with your vet first. Depending on the skin condition, medicated baths may help manage crusting, scaling, or secondary infections. Other dogs may need bathing postponed, particularly when topical medication has recently been applied.

Frequent washing will not make the mites disappear faster. It can also irritate uncomfortable skin. Our guide to how often to bathe an itchy dog explains how to approach bathing when your dog needs extra care.

Helping Dry, Irritated Skin Feel More Comfortable

Even after mite treatment begins working, your dog’s skin may remain dry, flaky, or uncomfortable for a while.

Once your veterinarian approves regular bathing, Jax n Daisy’s Anti-Itch Dog Shampoo can help calm everyday itching and dryness as part of a gentle recovery grooming routine.

For smaller dry or irritated areas between baths, our Dog Lotion for Dry Skin & Hot Spots can provide additional skin comfort. Both are supportive skincare products, not mange medications. Avoid applying additional products to open sores or infected skin without veterinary approval.

If scratching has already caused thick crusts or scabbing, our article on scabs on dogs explains why these changes deserve attention.

When Should You Take Your Dog to the Vet?

Do not wait for extensive hair loss before making an appointment. Have your dog’s skin examined if scratching continues, new bald patches appear, or affected areas begin spreading.

Seek prompt veterinary attention if you notice open sores, swelling, discharge, an unpleasant odor, rapidly worsening lesions, or changes in appetite and energy. If you suspect sarcoptic mange, limit contact with other dogs until your veterinarian advises on treatment and precautions.

Mange can look alarming, but it is treatable. Get the diagnosis first, finish the full treatment, and use supportive skincare only with your vet’s approval.