Dog Mange: Signs, Types and When to See a Vet

What mange usually means

Mange is a group of skin diseases caused by mites. VCA Animal Hospitals describes two main types that look different and behave differently. Demodectic mange, sometimes called red mange, is caused by Demodex mites that live in hair follicles and is the most common type in dogs. Sarcoptic mange, also called scabies, is caused by a mite that burrows just under the skin.

Most dogs carry a few Demodex mites on their skin without any trouble. VCA explains that the disease develops only when the immune system fails to keep the mite population in check, which is why it mostly affects young puppies and dogs with weakened immune systems. Sarcoptic mange is different: it can affect dogs of any age, including healthy adults.

Signs to look for

Demodectic mange typically shows as patchy hair loss, often without severe itching. In the localized form the hair loss is mainly on the face and front legs, while the generalized form involves many areas, especially the paws. Itching tends to appear only if a secondary skin infection develops.

Sarcoptic mange is mostly about itch. VCA says the mites cause intense itching, so affected dogs chew and scratch constantly, leading to heavy hair loss, especially on the legs and belly. Over time the skin can thicken and darken. Because other skin problems look similar, you cannot tell the type from appearance alone.

Is mange contagious?

It depends on the type. VCA says demodectic mange is not contagious to other animals or to people, since the mites are already present on most dogs and are passed from the mother to puppies in the first days of life. The condition does have a genetic component, so affected puppies often have affected littermates.

Sarcoptic mange spreads readily to other dogs and to people. VCA notes that the mites cannot complete their life cycle on people but can still cause severe itching until they die. If a family member develops an itchy rash, tell their doctor about the possible exposure. Keeping your dog away from areas frequented by infected dogs or foxes helps prevent infection.

When to call your vet today

Book a vet visit if you notice patchy hair loss, red or crusty skin, thickened or darkened skin, or constant scratching and chewing. Early diagnosis matters because the two types need different handling and because other skin conditions can look the same.

Call sooner if the skin looks raw, smells bad or is oozing, if your dog seems unwell or stops eating, or if the itching keeps your dog from resting. These can mean a secondary skin infection, which VCA notes is common in generalized demodectic cases and may need its own treatment.

When it is an emergency

Mange itself is rarely an emergency, but get urgent veterinary care if your dog is lethargic, refuses food and water, has a fever, or has widespread raw or infected skin. Puppies and senior dogs with a weak immune system can decline faster than healthy adults, so do not wait and watch.

If you are unsure whether the signs are urgent, call your vet or an emergency clinic and describe what you see. They can tell you whether the dog needs to be seen right away.

What you can safely do at home

Keep the dog away from other dogs until the vet has said what type it is, and keep your own hands washed after handling a very itchy dog. For sarcoptic mange, VCA advises discarding bedding where the dog sleeps or washing it frequently, and your vet can tell you what cleaning is right for your dog.

Do not apply home remedies, human skin products or another pet's treatment, and do not give any medicine without your vet's direction. Treatment choice depends on the dog's medical history and drug sensitivities, so a wrong product can do harm or only delay the right diagnosis.

Wash your dog's bedding often while treatment is underway; a washable dog bed makes that much easier.

What the vet will check

VCA says a veterinarian usually diagnoses both types by examining skin scrapings under a microscope. For demodectic mange a higher than normal number of mites confirms it, and a skin biopsy is sometimes used for chronic cases. For sarcoptic mange mites are often not found because they burrow deep, so a diagnosis may be presumed from the signs.

Treatment depends on the type and may involve oral or topical antiparasitic drugs, along with medicated shampoos or antibiotics for secondary infections. Generalized demodectic cases can take a long time and need repeated scrapings. VCA notes that relapses are common until about 12 to 18 months of age and should be treated promptly.

Prevention

You cannot fully prevent demodectic mange because it is tied to a young or weakened immune system and has a genetic component. VCA advises that affected dogs and their parents should not be bred. Good general care and prompt attention to skin changes give the best chance of an early diagnosis.

For sarcoptic mange, avoid places where infected dogs or foxes are known to spend time, and treat any in-contact dogs as your vet directs so mites are not passed back and forth. If your dog is still scratching four to five days after treatment, contact your vet.

This page is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your pet.