Is your dog losing hair or itching uncontrollably with no signs of fleas? If so, your dog may have mange. Mange is a term that gets thrown around a lot in the veterinary world and more often then not, what owners believe is mange turns out to be fleas that are just not visible. As most vets will tell you, it is always important to first rule out fleas before looking for other skin conditions. Your dog may have fleas, even if you can’t see them. Once fleas have been ruled, only then should an owner start to think that mange is the cause of their skin problems. Read more if you would like to learn more about this disease.
What is Mange?
Mange refers to a skin disease that is caused by parasitic mites. These mites are very tiny, and they can be dog-specific or can be zoonotic and infect other species, including humans.
Sarcoptes mites are the parasites that can cause scabies. Infected dogs can pass this mite to other pets and to people via contact, and it is a highly contagious mite. Cheyletiella is another contagious mite that is also known as “walking dandruff” because they can cause excessive flaking of the skin. Demodex mites can live in small numbers on the skin of a normal dog, but when the dog is very young or has a compromised immune system, then Demodex mites can be problematic. Dogs that have had a Demodex infection as a puppy should not be used for breeding purposes.
What Are the Symptoms?
The most common symptoms are itching and hair loss. Mites like Sarcoptes can cause pets to be extremely itchy because they are burrowing mites. Mites like Demodex live in the glands near hair follicles, causing hair to fall out, but they may or may not cause itchiness. Demodex can cause localized signs like hair loss around the face and limbs or can cause more generalized hair loss all over the dog’s body.
Frequently, skin can become inflamed when mites are present. This inflammation can make it easier for your dog to develop secondary bacterial skin infections. When left untreated, infections can compromise the skin’s ability to act as a barrier against bacteria and other outside invaders. In rare cases, these skin infections can cause severe illness, especially in very young puppies and dogs who are on immunosuppressive drugs like chemotherapeutic medications used for cancer treatments.
How Can I Tell If My Dog Has Mange?
Because skin mites are so small, microscopic exams are usually necessary to confirm the diagnosis. Your veterinarian may recommend a skin scraping test. This is where a blade is used to scrape the skin in an area where there is hair loss or other skin lesions. Superficial skin scraping is best for diagnosing Sarcoptes infestations while deep scraping to the point of minor bleeding is best for confirming a Demodex diagnosis.
If there are skin lesions in areas that are too difficult to scrape, i.e. around the eyes or in between the toes, then a trichogram can be performed. This involves plucking a hair sample from your pet, putting it on a slide with mineral oil, and evaluating it under a microscope. Trichograms are another effective way to diagnose Demodex. In the case of Cheyletiella mites, a piece of Scotch tape can be applied to the skin and fur, picking up mites in the process. The tape can then be applied to a slide and examined with a microscope.
What If It’s Not Mange?
Itchy dogs with hair loss can have other skin diseases besides mange. Environmental and food allergies are some of the most common skin disorders in dogs. Itching, hair loss, and skin infection can occur whenever a dog encounters grass, pollen, weeds, etc. Skin lesions can be localized or generalized. Food allergies are more likely to cause generalized signs, including ear infections, while environmental allergies may be more localized to the feet and belly. Fleas are another kind of skin parasite that can cause intense itching, and some dogs can develop an allergy to flea bites. For more information, check out our article on Dog Allergies.
Fungal infections like ringworm can cause red skin lesions, hair loss, and severe itching. Ringworm is highly contagious and can be passed from dogs to other pets and people. Disorders of the endocrine system can also cause hair loss. Cushing’s disease, an adrenal gland disorder, can cause white crusted lesions and make it harder for dogs to fight off infections. Thyroid disorders like hypothyroidism can also cause hair loss and secondary skin infections. Autoimmune diseases and even skin cancer can cause similar lesions, and these may be suspected if treatments for other skin conditions are not effective.
How is Mange Treated?
There are topical and oral medications available for mange treatment. Some are recommended based on age and severity of the infestation, and your veterinarian may recommend one or several treatments based on your dog’s clinical signs. If a skin infection is present, then a combination of topical and oral antibiotics may also be prescribed.
Lime sulfur dip is a liquid lime solution that is applied to a dog’s skin for mange and ringworm treatments, and it is usually recommended for use one to two times a week for four weeks. Because of sulfur as an ingredient, it has a strong rotten-egg smell and can stain fabrics easily. However, it is very safe for animals that are too young to use other medications. Dogs that can become ill from ivermectin-containing products should use lime sulfur dips for their mange treatment.
Ivermectin is an oral anti-parasitic medication that is commonly prescribed for Demodex mites. It has a low margin of safety for very small dogs because it is difficult to dose in small amounts without coming too close to toxic doses. Overdoses can cause gastrointestinal and neurologic issues, including seizures. Moxidectin is in the same drug class as ivermectin but is available in a topical form that has a lesser risk of side effects. Flea and tick preventives like Bravecto are being used off-label for Demodex treatment and are highly effective according to recent studies1.
If your dog is very itchy or experiencing hair loss, then remember that mange may be the cause and can be contagious depending on the type of mite present. Be sure to handle your dog with caution, wash your hands after petting him, and keep him out of your bed and off your furniture until you can rule out a mite infestation via testing at your veterinarian’s office. It can be very frustrating to see your dog itching so much, but by quickly diagnosing mange, you will be able to prevent a severe skin infection and help your dog feel better faster!
- Efficacy of orally administered fluralaner (Bravecto™) or topically applied imidacloprid/moxidectin (Advocate®) against generalized demodicosis in dogs. Parasitology & Vectors, 2015 March 28, 8:187.