My son is having Biocare Baby Bioflora as recommended by a chiropractor as he'd had antibiotics a few weeks before x
I’ve been using these drops from the beginning and my boy has never really had any gut issues. I can’t say if they’ve actually helped or not on that front, but they contain vitamin D and breastfed babies are supposed to get a vitamin D supplement anyway, so this is the one I use. https://amzn.eu/d/9peayfW I tend to pump once or twice a day, so I put a few drops in his bottle, but you can put the drops on your nipple and administer it that way. It’s worth noting that I had a C-section, so my babe didn’t get exposed to all that good bacteria in the birth canal like your baby did - that’s so important to forming their microbiome. And even though you had some antibiotics, it won’t have made your milk sterile - he’ll still be getting lots of helpful bacteria from you.
We're using Kendamil baby drops from the begging and never had any issues. you can check them on their website
Hey look into Biogaia and Activated probiotics they’re both good brands. Also don’t forget that breastmilk will very nicely help populate their gut with good bacteria x