I'm going to sound like a turmeric advocate, but I looked it up on Wikipedia and I guess it's pretty effective on cystic acne, you might look it up youself =)
Also, I've use the AcneFree system which is like a cheaper version of Proactiv and it seems to work fine. But I figure something cheap and natural is worth a shot.
19yr old female diagnosed with UC (pancolitis) in 2005 at age 15
125mg Azathioprine 1xday / 1 Mesalamine enema every night /
2000mg Fish Oil 1xday / 500mg Turmeric 3xday /
450mg Boswellia 1xday / 400IU Vitamin E 1xday
Arthritis in both knees
Also: asthma, acid reflux, and Reynaud's Syndrome