The probiotic my doc recommended comes with FOS. I think its called HMF and its so freakin expensive. Its in powder form. She believes the powder form is better and says it must be refrigerated. I just started this about a week ago so we'll see how it goes. It was $50 for this little container that should last about 6-8 weeks..I think. I'm taking an extra dose now due to strep and antibitics so who knows how long I will have it. You know...I thought I'd have a yeast infection by now with the antiobitocs...I always got one shortly after starting them and I have no sign of it. I wonder if these probiotics are helping.