Acne in cats is usually on the chin but the lower lips may sometimes be affected. It may look like red spots, papules, or crusty areas and occasionally the chin may swell up markedly. In very severe cases of acne the lesions may look quite aggressive and the hair on the chin may be lost; the cat may also show signs of being in pain.
Some cats may just have one episode of acne in their lifetime, but for many patients it is a recurrent problem which may vary in severity and frequency of recurrence. Poor grooming, an abnormality of sebum production or a keratinization problem of the skin are thought to cause acne in cats.
Usually this condition is easily diagnosed 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 a tumour.
This condition is often treated with antibiotics such as enrofloxacin, amoxycillin/ clavulanate or cephalexin. Shampoos, cleansers or other skin treatments (usually gels or ointments) may also be used. These are often products containing ethyl lactate, benzoyl peroxide or sulpher-salicylic acid all of which help with abnormalities of keratinization, but do take care as some of these products can be irritating when used on cats. Shampoos are often applied once or twice a week, at least initially.
The treatment should be used until the lesions have all healed and then gradually reduce the frequency of treatments such as shampoos or ointment applications. Once you and your vet have discovered how often the problem recurs in your cat an individual treatment protocol can be designed to try to keep the condition under control. Often cleansing the chin area regularly with shampoos or ointments may extend the time between relapses of this condition.
The prognosis in these cases is usually quite good but do consider it as possibly a long term problem requiring control of the symptoms rather than a complete cure.