Mine just told me stick with the neutropenic diet for a bit and as the diarrhea subsides, reintroduce normal foods... I'm a year out from my sct and still have trouble with some foods.
I also took this as an opportunity to change my diet for the better but don't worry life gets better...

Valerie, you will need to run it by your transplant doctor first. They only wanted me to take children's probiotics cause my counts were still low

If you are on maintenance Revlimid after your SCT I would definitely take a probiotic. Revlimid can cause severe diarrhea. If the problem persists I would ask your doctor about adding a daily bile acid sequestrant such as Colestipol or Colesevlam. Cheers,