As far as I know, there are very few medications that are approved for babies under a year. Only b/c it’s hard to get people to volunteer their kids for studies at such a young age. But, many MANY docs prescribe this med and there are studies and evidence that it can be given to babies, even small babies. I would also print out the marci-kids info, or ask your doctor to check his own research using up-to-date, if he has access, or the Harriet Lane handbook, or to consult a GI. If he doesn’t budge, maybe you can look into getting a new doc, or ask for a referral to a ped GI. My daughter started with zantac at 8 weeks, moved to compounded prilosec at 9 weeks, to prilosec in CaraCream, and finally to prevacid in CaraCream. We have moved up in dose, to a max dose around 42mg prevacid, but mostly around 30mg, and now are down to 15mg once a day. Good luck.