My doctor has prescribed Isentress and Viread to begin taking them at the same time. It seems most people on this forum begin one drug and a week later start another. My doctor believes resistance could occur in one week if only one drug is taken. She is basing it on her experiences with HIV since not much is known about Xmrv. Has anyone done it this way and what were the results. I am happy and excited over the possibility of getting better but, also, afraid of the potential side effects of the drugs.