Acne in dogs is usually on the chin and lips. It may look like red spots, papules, or crusty areas and occasionally the chin may swell up. A secondary bacterial infection is sometimes present, especially in advanced cases. The area is often painful for the dog and the lesions may cause scarring.
Usually this condition is easily diagnosed on clinical signs but occasionally a biopsy may be performed. This will allow the vet to ensure that the lesions are not caused by another problem such as ringworm, demodex or an allergy.
This condition is often treated with antibiotics. Cephalexin is very useful when there is a deep secondary bacterial infection. The antibiotic treatment is often needed for 6 - 8 weeks. Shampoos, cleansers or other skin treatments (usually gels or ointments) may also be used. Benzoyl peroxide shampoo or gel is helpful as it has antibacterial properties and will reduce the bacterial numbers on the skin. Sometimes corticosteroids may help to reduce the inflammation, but long term use is best avoided. It is a good idea to try to limit behaviour which may aggravate the condition such as rubbing the chin along the floor and chewing toys or bones which makes the skin wet with saliva. Never try to pick at or pop the pustules as this can lead to a worsening of the problem.
Sometimes long term treatment is required for this condition.