Looking for advice re baby reflux

Karee
My little one is 4 months old, EBF and rarely keeps her meals down. She has gained 2 oz in one month and yesterday the Dr said it's time to start acid reflux medicine. Normally I am anti medicine but considering the circumstances, I think it's necessary. My husband, on the other hand, does not. He wants her to start being bottle feed with rice cereal added to my breast milk. I've talked to a few people that say adding rice cereal this early can have negative effects on their GI track since it's adding in something her body doesn't need for another few months. I desperately want to continue breastfeeding since I was unable to do so with my first child. I am struggling with taking myself out of the equation and solely thinking of my daughter's best interest. I asked my pediatrician about adding probiotics to help quicken milk digestion and she said they might help but that there have not been enough studies to prove they make a difference. I don't know what to do nor how to handle the argument between me and my husband (we never argue) about whether or not to medicate for a few months. Any help out suggestions would be appreciated.