I just completed 14 months of Clofazimine along with Azith and Ethambutol. It took care of the Mac and I had a nice tan even in Winter. I can no longer take Rifampin as it caused acute kidney failure and I lost 50% of my kidney function. But the clofazimine did its job quickly and I have been MAC free for over a year now. I did have a little trouble with upset bowels but not nearly as much as the side effects from Rifampin. Was it worth it? Absolutely.