Hello Jayney8
I had really bad skin until I was 30, and it really used to get me down.
I have taken both oxytetracycline and erythromycin orally in the past. Both quite effective.
From memory the oxytetracycline was fine, I don't recall any ill effects but you have to take it on an empty tummy to get full effect which was a bit of a pain!
RR xx