Umm...i'd absolutely quit the anti-biotics. Anyone advocating their use for the treatment of acne hasn't spent enough time hearing about the nightmares of coming off of them. They are only effective while you take them, whether it's 3 weeks, or 3 months, or a year. Either way, when you come off of them, if you haven't addressed the underlying cause of your acne, you'll be right back where you were, and likely worse. A good quality probiotic blend can actually overwhelm the bad bacteria in your gut naturally.
I've heard great things about Burdock Root as a blood cleansing agent/treatment for acne. Dandelion Root, Red Clover, Sheep Sorrel, Slippery Elm Bark, White Willow Bark, Turkey Rhubarb, and so many other herbs are great for cleansing your blood/liver. I remember a thread i was reading a while back where the only thing that the person changed in his approach to fighting acne was adding a Burdock Root supplement. And it got him clear. You can make a tea using all these ingredients and drink it every day throughout the day. This alongside a healthy diet change and i suspect you'll see results. Granted you can never be certain from person to person, but it's a super healthy thing to do for your body either way.
Cleansing the liver is one of, if not the healthiest things you can do for overall health. It's the number one filtration organ we have, and when it can do it's job efficiently this means great things for your other organs and body functions