I have been on the 6MP for several years, when I was first diagnosed with CD they had me on this along with pentasa and the combo of those made me lose my hair also. So, I went off all meds cuz the crown of my head was completely bald, but just being on the 6MP, I havent lost any hair. I use this and getting ready to start the cimzia shot tomorrow, was on humira and started having a flare up for about the past month. On prednisone till the shot kicks in. I have had no side effects with the 6mp by itself....labs need to be checked at least every 3 months...hope it works for ya!!