No. Not for C. diff.
Doc, different strains of probiotics do different things in your gut. Acidophilus is wonderful and you need it because you are on antibiotics AND you have Crohn's. You want to constantly introduce the good bacteria to crowd out the bad. Take it for the rest of your life.
Florastor is one--and only one--strain of a DIFFERENT probiotic. This strain is NOT in your acidophilus probiotic. It is important because it has been PROVEN to help fight C. diff infections. I would take it and STAY on it for months to come (6-12?)--until you're sure your C. diff will not return. If you have insurance, your doctor may be able to write a prescript
ion for Florastor--I'm not sure. If so, it might not cost much at all. If you don't have insurance that will cover it, you can go to your local health food store and request a probiotic with the SAME EXACT STRAIN as Florastor: Saccharomyces boulardii. If it were me, I would just pick up the phone, call my GI's office and ask. It never hurts to ask.
Take them both!
Here's a Florastor link: http://www.florastor.com/article.asp?id=1140