Mange is one of the most uncomfortable skin conditions a dog can develop — and one of the most commonly misunderstood. The word alone can cause alarm, but mange is a treatable condition and most dogs recover fully with appropriate veterinary care. Understanding the two main types of mange — and why they are so different from each other — is essential to understanding what your dog is dealing with and what to expect from treatment.
If your dog has been scratching intensely, losing hair, or developing skin lesions, contact Walker Lake Veterinary Centre at (587) 786-6771 for an assessment.
Mange is not a single condition — it is a term covering several distinct diseases caused by different species of mites. The two most important types in dogs are sarcoptic mange and demodectic mange, which have different causes, presentations, levels of contagiousness, and treatment approaches.
What Is Mange?
Mange refers to skin disease caused by microscopic mites that live on or in the skin. Depending on the species, mites may burrow into the skin layers, live in hair follicles, or reside on the skin surface. Their presence causes skin inflammation, intense itching, hair loss, and secondary bacterial infection.
All dogs have some mite species on their skin as part of the normal skin microbiome — mites only cause disease under specific circumstances related to immune function, infestation level, and the specific species involved.
Sarcoptic Mange — Scabies
What Is Sarcoptic Mange?
Sarcoptic mange is caused by Sarcoptes scabiei var. canis — a microscopic mite that burrows into the superficial layers of the skin. It is one of the most intensely itchy conditions in veterinary medicine and is highly contagious between dogs and to other species including humans.
How Sarcoptic Mange Spreads
Sarcoptic mange spreads through direct contact between animals. Common sources include:
- Contact with infected dogs at dog parks, boarding facilities, grooming salons, or training classes
- Contact with wildlife — foxes are a significant reservoir of Sarcoptes scabiei in Alberta and urban areas around Edmonton
- Contaminated bedding, grooming equipment, or kennelling
Sarcoptes mites can survive off the host for 2 to 6 days in the environment. This means that a dog can acquire sarcoptic mange from areas where an infected dog has been, without direct contact.
Signs of Sarcoptic Mange
The hallmark of sarcoptic mange is intense, relentless itching — out of all proportion to what would be expected from the visible skin changes, particularly in early stages.
- Intense pruritus — scratching, rubbing, and biting that does not respond to normal treatments
- Initial lesions typically appear at the ear margins, elbows, hocks, and ventral abdomen — areas with less hair and closer skin-to-ground contact
- Small red papules and crusting at affected sites
- Progressive hair loss as the condition spreads
- Thickened, crusted skin — particularly at the ear margins, elbows, and hocks in chronic cases
- Secondary bacterial infection producing pustules and deeper skin changes
- The dog may appear thin and depleted from the constant stress of severe itching
The Pedal-Pinna Reflex
A characteristic clinical sign of sarcoptic mange is the pedal-pinna reflex — when the ear margin is rubbed or scratched, the dog reflexively scratches with the hind leg on the same side. This reflex is positive in approximately 75% of dogs with sarcoptic mange and is a useful clinical indicator, though not definitive.
Sarcoptic Mange in Humans
Sarcoptes scabiei from dogs can transiently infect humans, causing an itchy rash — typically on the arms, torso, and areas that come into contact with the dog. Human infection is self-limiting — the mite cannot complete its life cycle on humans and the infestation resolves within 2 to 5 weeks once the dog is treated. However, it causes significant discomfort in the interim and human family members should be aware of this possibility when a dog is diagnosed.
Diagnosing Sarcoptic Mange
Sarcoptic mange is notoriously difficult to diagnose definitively. The mites burrow deep into the skin and are present in relatively small numbers, making them difficult to find on standard skin scrapings.
Skin Scraping
Multiple deep skin scrapings from several sites are examined microscopically for mites, eggs, and faecal pellets. A positive finding confirms sarcoptic mange, but a negative result does not rule it out — sensitivity of skin scraping for sarcoptic mange is estimated at only 20 to 50%.
Serology
A blood test detecting antibodies to Sarcoptes scabiei is available and provides a more sensitive diagnostic tool than skin scraping. A positive result supports the diagnosis.
Therapeutic Trial
Because of the low sensitivity of skin scraping, many veterinarians treat suspected sarcoptic mange empirically — the dog is treated with an appropriate anti-mite medication and improvement in response to treatment confirms the diagnosis. This approach is commonly used in practice.
Treating Sarcoptic Mange
Effective treatments for sarcoptic mange include:
Isoxazoline Antiparasitic Products
The most effective and convenient treatment currently available. Products in this class — including fluralaner (Bravecto), sarolaner (Simparica), and afoxolaner (NexGard) — are highly effective against Sarcoptes mites. A single or two-dose course typically resolves sarcoptic mange completely within 4 to 8 weeks. These products are also used for routine flea and tick prevention.
Selamectin
A topical spot-on product applied to the skin at the back of the neck. Two to three doses given 2 to 4 weeks apart are typically required. Also effective against ear mites and heartworm prevention.
Treating All In-Contact Animals
All dogs in the household must be treated simultaneously — even those not showing signs, as they may be subclinically infested and will reinfect treated dogs.
Environmental Decontamination
Wash all bedding, blankets, and soft furnishings at 60°C. Vacuum all surfaces the dog frequents. Sarcoptes mites do not survive long in the environment, but reducing the environmental burden supports treatment success.
Treating Secondary Infections
Secondary bacterial skin infections — which are almost universally present in established sarcoptic mange — require treatment with systemic antibiotics alongside the antiparasitic medication.
Demodectic Mange — Demodicosis
What Is Demodectic Mange?
Demodectic mange is caused by Demodex canis — a cigar-shaped mite that lives in the hair follicles of dogs. Unlike Sarcoptes, Demodex mites are a normal component of the dog’s skin microbiome — virtually all dogs carry small numbers of Demodex mites acquired from their mother during the first days of life.
Demodicosis occurs when the mite population grows beyond what the immune system can control. This happens in two contexts — in puppies with immature immune systems, and in dogs with significant immune suppression from disease or medication.
Is Demodectic Mange Contagious?
Unlike sarcoptic mange, demodicosis is not contagious between adult dogs under normal circumstances. The mites are transmitted from mother to puppy during nursing but do not spread between adult dogs in normal social interaction. There is also no evidence that Demodex canis infects humans.
Types of Demodicosis
Localised Demodicosis
Affects limited areas — typically one to five discrete patches of hair loss, most commonly on the face around the eyes and muzzle, and on the forelegs. The skin in affected patches may be slightly red and scaly but is typically not intensely itchy — this distinguishes localised demodicosis from sarcoptic mange.
Localised demodicosis occurs predominantly in puppies and young dogs between 3 and 18 months. In many cases it resolves spontaneously as the immune system matures, without treatment. Approximately 90% of localised cases resolve on their own within 6 to 8 weeks.
Generalised Demodicosis
Involves large areas of the body or five or more affected sites. It is significantly more serious than localised disease and requires active treatment. Generalised demodicosis in a puppy or young adult dog suggests a more significant immune deficiency. Generalised demodicosis developing in a middle-aged or older dog — adult-onset generalised demodicosis — almost always has a significant underlying immunosuppressive condition driving it.
Common underlying conditions associated with adult-onset generalised demodicosis include:
- Hyperadrenocorticism (Cushing’s disease)
- Hypothyroidism
- Diabetes mellitus
- Neoplasia
- Long-term corticosteroid or other immunosuppressive medication
Any adult dog developing generalised demodicosis for the first time should be thoroughly investigated for an underlying cause.
Signs of Demodectic Mange
Localised Demodicosis
- Circular patches of hair loss — typically 1 to 4cm in diameter
- Mild redness and scaling of affected skin
- Commonly affects the face — around the eyes, on the muzzle — and the forelegs
- Minimal or no itching in uncomplicated cases
Generalised Demodicosis
- Extensive, multifocal or diffuse hair loss
- Significant skin inflammation — redness, scaling, thickening
- Secondary bacterial infection (pyoderma) — often severe, causing painful draining lesions
- Intense itching when secondary infection is present
- Enlarged lymph nodes in severe cases
- Systemic illness — lethargy, fever, reduced appetite — in dogs with severe secondary infection
Diagnosing Demodectic Mange
Skin Scraping
Multiple deep skin scrapings are performed, squeezing the skin firmly while scraping to extrude mites from the hair follicles. Demodex mites are typically present in large numbers and are found readily on scraping in most cases — unlike Sarcoptes. Finding large numbers of mites — particularly immature stages — confirms active demodicosis.
Trichogram
Hairs plucked from affected areas and examined microscopically for mites attached to the hair bulb. A useful quick screening test.
Biopsy
Occasionally used in cases where scraping does not yield mites but demodicosis is strongly suspected — for example in areas with thickened, fibrotic skin where scraping is difficult.
Treating Demodectic Mange
Localised Demodicosis in Puppies
Many cases in young dogs resolve spontaneously. Active treatment is not always required but the puppy should be monitored closely for progression to generalised disease. If lesions are not improving within 6 to 8 weeks or are spreading, treatment should be initiated.
Isoxazoline Products
As with sarcoptic mange, isoxazoline antiparasitic products have transformed the treatment of generalised demodicosis. They are highly effective against Demodex mites and represent the current treatment of choice. Monthly dosing is continued until two consecutive negative skin scrapings confirm resolution — typically 2 to 4 months for most cases.
Amitraz
A topical treatment applied as a whole-body dip. Highly effective but requires careful handling — amitraz is toxic to cats and humans and requires appropriate protective equipment during application. It has largely been replaced by isoxazoline products in routine clinical use.
Treating Secondary Infections
Secondary bacterial pyoderma — almost universally present in generalised demodicosis — requires systemic antibiotic treatment alongside antiparasitic therapy. Medicated shampoos reduce bacterial load on the skin surface.
Addressing the Underlying Cause
In adult-onset generalised demodicosis, identifying and managing the underlying immunosuppressive condition is essential. Treating the mites alone without addressing the underlying cause results in recurrence.
Long-Term Monitoring
Dogs with generalised demodicosis require monthly skin scrapings during treatment to monitor response and confirm resolution. Treatment is continued for at least one month beyond the first negative scraping. Premature discontinuation of treatment is a common cause of relapse.
If your dog is losing hair or scratching intensely, book an appointment at Walker Lake Veterinary Centre. We can perform skin scrapings and identify the cause. Call (587) 786-6771 or book online. Located at 5109 22 Avenue SW, Southwest Edmonton.
Book an Appointment at Walker Lake Veterinary Centre
Walker Lake Veterinary Centre provides skin scraping, cytology, and comprehensive treatment for mange and other parasitic skin conditions in dogs across Walker Lake, Summerside, Ellerslie, Heritage Valley, and Southwest Edmonton.
Call us at (587) 786-6771 or book online. We are located at 5109 22 Avenue SW, Edmonton.
Clinic hours:
- Monday, Tuesday & Thursday: 9:00 AM – 7:00 PM
- Wednesday & Friday: 9:00 AM – 6:00 PM
- Saturday: 9:00 AM – 3:00 PM
- Sunday: Closed
Frequently Asked Questions
How do I know if my dog has sarcoptic or demodectic mange?
The two types have overlapping signs but key differences. Sarcoptic mange causes intense itching — often the dominant feature — and typically starts at the ear margins, elbows, and belly. Demodectic mange causes hair loss that may be minimally itchy in uncomplicated cases and typically starts on the face and forelegs of young dogs. Skin scrapings and the clinical picture together guide the diagnosis. Your veterinarian may treat empirically for sarcoptic mange if clinical suspicion is high even with negative scrapings.
Can my dog get mange from a fox?
Yes. Foxes are a common reservoir of Sarcoptes scabiei in Alberta. Dogs that have contact with foxes — or visit areas where foxes have been — are at risk of acquiring sarcoptic mange. If your dog has been in contact with a fox and subsequently develops intense itching, mention this to your veterinarian.
Will my dog’s hair grow back after mange?
In most cases, yes. Once the mite infestation is controlled and secondary infections have resolved, hair typically regrows over several weeks to months. In areas of severe, chronic inflammation — particularly in long-standing generalised demodicosis — some permanent scarring may prevent complete hair regrowth in affected patches.
Is mange painful for dogs?
Sarcoptic mange causes intense itching that is deeply uncomfortable and distressing — the constant scratching, rubbing, and biting causes physical exhaustion and significant secondary skin damage. Generalised demodectic mange with severe secondary bacterial infection is also painful. Both conditions significantly impact quality of life and require prompt treatment.
My puppy has small bald patches — is this mange?
Small bald patches on the face and forelegs of a puppy between 3 and 18 months are a classic presentation of localised demodicosis. However, other conditions — ringworm, folliculitis, and alopecia from other causes — can look similar. A veterinary assessment including skin scrapings will confirm the diagnosis. Localised cases in puppies often resolve without treatment but should be monitored for progression.
