With BF babies an empty stomach is about 2 hours after a feed. However, in theory since you’re on a compound you shouldn’t have to wait to medicate. The purpose of compounding meds is so that there isn’t the need for an empty stomach or waiting 30 mins to feed. Although, I have to say my DDs GI DID say that even w/compounds you should still wait 30 min to give the med time to get into their system. I think it depends on the baby and that may also be why parents notice a decrease in effectiveness over time. JMO, give it a try and if things seem worse then you know for your LO they need that time for the med to start working before being fed. Also, you may want to consider switching to something like Zegerid where timing is not necessary. HTH!