Acnee on the posterior

Patient: Hello!I’m a 23 years old female and I have problems with acne on my posterior. It’s highly unsightly and sometimes, around the time of my period, the zips get infected and can become painful. There are even those zips that have a root under the skin. I think they’re called nodulocystic acne. I have periods when I sit a lot on chairs and such but not all the time and I didn’t notice any change in the severity of the affected portion.What can I do to get rid of it? I would prefer for the treatment to be without heavy medication if possible.Thank you!