Overview of Canine Acne
Canine acne is a benign self-limiting disease of the chin and lips of young dogs. Short-coated dogs, such as boxers, bulldogs and rottweilers, are at increased risk for acne. The condition starts at puberty around 5 to 8 months of age. Most dogs improve with age and the condition typically resolves after one year of age.
The exact pathogenesis has not been established. Genetics, hormones and trauma have been hypothesized to play a role.
What to Watch For
Signs of Acne in Dogs may include:
Red bumps (papules) and blackheads (comedones) are usually noted on the chin and lips of young dogs. They may become infected and pus can be expressed from these lesions.
When infection is present itching may develop and the dog may start rubbing his face against carpet and furniture.
Diagnosis of Acne in Dogs
A clinical diagnosis of acne is usually made considering the breed, the age of onset and appearance of the lesions. However, there are other diseases that may look similar to acne that need to be ruled out.
Demodicosis. This is a non-contagious type of mange, and it is important to do skin scrapings to rule out the possibility of demodicosis. Your veterinarian will scrape an area on the chin until there is some capillary bleeding and then examine the material under a light microscope.
Ringworm (dermatophytosis). This disease may also start with lesions resembling acne, so a fungal culture may be necessary. Hairs are plucked and submitted for culture, and results are available in 10 to 14 days.
Puppy strangles. This is another disease that could start with lesions similar to the those seen with acne. The main difference is that, animals with puppy strangles are depressed and anorexic (poor appetite), while dogs with acne are otherwise healthy.
Treatment of Acne in Dogs
The treatment for acne is typically topical treatment. Some gels are similar to those people use for acne, like benzoyl peroxide. It is important that you use only the products recommended by your veterinarian, as your dog’s skin is thinner and more sensitive than yours. The average product containing benzoyl peroxide for human acne contains 10 percent benzoyl peroxide while the maximum concentration that could be used on a dog is 5 percent.
Some treatments may include:
Washes containing benzoyl peroxide twice weekly. Only veterinary products should be used. Most shampoos contain 2.5 percent benzoyl peroxide, such as Oxydex® shampoo.
Some dogs may benefit from topical antibiotics like mupirocin to limit the secondary infection. These products should be used twice daily and gently massaged on the area until completely absorbed.
Topical steroids may be used to decrease the swelling and the inflammation on the area. Gloves should be used when applying these products.
In severe cases systemic therapy may be necessary and you will need to administer pills once or twice daily for a prolonged period of time.
Antibiotic therapy like cephalexin may be necessary for 6 to 8 weeks in chronic cases.
Retinoids are not usually used in dogs with acne, as the formation and development of canine acne appears to be different from people’s acne.
Trauma should be avoided to limit scar formation. You may be required to apply antibacterial lotions or ointments.
In-Depth Information on Canine Acne
Acne is a disease of young dogs of short-coated breeds. Dobermans, bulldogs, Great Danes, boxers, German shorthaired pointers and rottweilers appear to be over-represented.
This disease is a localized folliculitis, which is an inflammation of the hair follicle, and furunculosis or rupture of the hair follicle restricted to the chin and lips. Comedones are the first lesions noted on the chin. They result from follicular dilation and plugging with excessive keratin formation. Erythema and alopecia may be present in more advanced cases.
Papules, pustules, firm nodules and fistulous tracts may develop as a consequence of a bacterial infection such as folliculitis and furunculosis. Lesions ulcerate and discharge a purulent exudate. Swelling of the chin is variable but it could be severe in some animals.
Regional lymphadenopathy may be prominent and pain and itchiness may be intense in animals with a secondary skin infection. Cysts may develop in chronic cases.
Clinical Presentation of Dogs with Acne
Onset of the disease occurs between 5 and 12 months of age. Acne in dogs tends to improve with age. Occasionally, it may persist in adulthood.
Erythema (redness), crusted papules and furuncles develop on the chin and lips. Hair follicles appear to be plugged (comedones or black head) with keratin.
With secondary infection, draining tracts may develop and exudate may be present.
In chronic cases secondary depigmentation may develop.
Differential diagnoses for this presentation include juvenile onset demodicosis with a secondary bacterial infection, dermatophytosis, contact dermatitis, and early stages of mild juvenile sterile granulomatous dermatitis and lymphadenitis (puppy strangles).
In contrast with juvenile cellulitis, dogs with acne do not have lymphadenopathy, and lesions are not present on the pinnae. In addition, dogs with acne are not systemically ill.