Reflux and sleep

My baby is 2.5 months old and has pretty bad GERD and gas. He's on Prevacid and carafate .. I am also dairy and soy free.... My question to you mamas out there is how do you get your gassy reflux babies to sleep longer??? Do you feed them differently during the day or what is your night time routine? Anything would help!

(I know my lo is capable of sleeping longer at night he was regularly sleeping 5 hrs stretches than a 3 hr stretch before we would get up for the day.. But his reflux has gotten extremely bad)