weaning off omerprazole for 4mth bb

Hi, my son (4.5m) has been on omerprazole for silent reflux. 2.5ml twice a day. We are hoping to wean him off the medicine (dr recomm trying it at 5mth)but also understand that there will b acid rebound for abit. Do u have any experience weaning off omerprazole gradually? N if so how and how long will the rebound effects last?thanks!!