so my son is 4 1/2 months old, 5 months on the 15th, he used to sleep pretty good, would wake like every 5 hours, maybe 2x a night, the past 3 nights he wakes to eat 5 ounces every 2 to 3 hours!!!!!!this is crazy, i just got my toddler to sleep most the night!
if its not one its the other!!;)

he might just be hungry.... have you tried giving him more formula at a time? i recall my oldest daughter was up to 6 ounces at a time by 4 months and 8 ounces by 6 months. she also had started cereal and jar food by 4 months and by 5 months was eating 2 jars a day, and i put cereal in her nighttime bottle. she was just a very active kid who burned a lot of calories each day, and needed more to eat! might be something to consider with your baby too?

i have tried 6 ounces instead of 5 and he dont eat it all, he eats a jar of food before bed, and 4 ounces of formula. last night i realized, when he woke up at 5, he didnt want to eat, or play he went back to sleep, i think he is getting woke up because he scoots up to the top of the crib and ends up in the corner, that or i go in and he is on his back and woke sleep on his back, he can roll both ways but too lazy at night i guess