My friend just said i need to run to the dr for antibio's for my 7 day long sinus infection. i had c diff and want to avoid that. who's right?

Both: You are both right. It will be a good idea to have your sinus infection checked and have a treatment plan, most sinus infections do not need antibiotics. You are right also being afraid that possible antibiotic treatment may result in reactivation of your C diff colitis. I would recommend that you let your doc know and let him or her worry about treatment complications.