Yes, erythromycin ointment mainly has an anti-inflammatory effect. After cats suffer from black chin, they can first use salt water, soapy water, etc. to clean and sterilize, and then apply erythromycin ointment for treatment, and the cat will be cured in 5-7 days. There will be obvious effects. It is normal for cats to have a black chin, just like humans have acne during adolescence. It will get better as long as you keep applying medicine.