Please pay special attention to the red part of the patient and be sure to protect yourself from the sun. 1. Reactive acne: A transient aggravation may occur 1-3 days after treatment (i.e. reactive acne), which generally subsides on its own and requires no special treatment. 2.Redness and swelling: Redness and swelling appear 1-2 days after treatment, which is normal. 3, superficial erosion: superficial erosion surface may appear at the treatment site, can be applied externally fusidic acid cream 1 time / day. 4, peeling: may appear about 1 week after treatment, peeling, can use cold compress and external moisturizing cream to relieve. 5.Pigmentation: pigmentation is likely to occur at the treatment site, which is a normal phenomenon and generally fades away on its own after a few weeks to a few months; during this period, attention must be paid to sun protection, avoid direct sunlight, sunscreen when going out, preferably with a sun hat, which can avoid aggravation of pigmentation and accelerate the fading of pigmentation. 6, sun protection: 1-2 days after treatment need to avoid light (mainly to avoid direct sunlight), apply sunscreen, with a sun hat, etc. to reduce photosensitivity reaction. 7. Pus overflow: If cystic acne has pus overflow from the lesions, there is no need to be nervous, just wipe away the pus and apply fusidic acid cream twice/day.