Dermatology clinic specializing in acne treatment

My teenage son's skin has been significantly damaged due to acne.

I received treatment at the dermatology clinic in front of my house for about two months last year, and although there was some improvement, my child's eating habits haven't improved much. They mostly like ramen, ham, and instant foods, so it was difficult.

However, during puberty, hormones are very active, and I developed acne below my chin more than last year, which is red and filled with pus, making it hard to describe. I already have scars on my face.

So far, I have visited three dermatology clinics in Yeosu, but I haven't seen good results yet.

What are good methods for acne treatment and which dermatology clinics are reputable?