Hello K.,
Fortunately we didn't have to resort to a PPI (Proton Pump Inhibitor) like Prevacid for our children's mild reflux, but I do want to tell you a bit how they work and when you should administer them. I used to be a pharm rep selling Protonix (not indicated for children), similar to Prevacid. Basically, the PPI works by preventing the proton pump (in your stomach) from producing certain acids once you start eating or drinking. Therefore, you ALWAYS want to give a PPI BEFORE food or liquid because it will cut down significantly on that acid, thus preventing the burning. As adults, Protonix is to be taken as soon as you wake up, before you even think about that first cup of coffee or smell that bacon because the pumps will start doing their thing! I'm assuming it's the same concept for children!
Definitely elevate the head of the bed too. Watch what you eat if you're breast feeding, or stir (don't shake) the formula to prevent bubbles. Hope this helps. Good luck!!