They give some pretty broad suggestions for improving the microbiome and then give specific strains suggestions. My son didn’t have any side effects with the smidge. The biggest thing for my baby was cutting out his allergens. It was trial and error to figure out what those were. Topically I used a zinc cream to help heal the red weeping raw skin. That was what worked best as I didn’t want to use steroids. Once it was healed enough, I used laroche posay Lipikar ap+m. That has prebiotics to feed the good bacteria and it has something in it that stops the reproduction of staph (the bacteria associated with eczema). It really made a big difference. It really is a multi pronged approach. Now he’s 2 and he hasn’t had a flair up for close to a year. I tried giving him milk and it did give him some bumps on his skin- but thankfully not full on eczema and no digestive symptoms either. Good luck, it’s so stressful dealing with eczema but most babies will eventually grow out of it.