Nipple flow on bottles

[Mayan]

When do you replace the nipples on your bottles from slow flow to a higher flow?
DS is almost 5 months, weighs 16 pounds and is eating about 30 OZ expressed breastmilk a day.
Sometimes he just seems to be annoyed at the bottle and I'm wondering whether he's tired of breastmilk :) or just needs a higher flow. Also he sucks so hard the nipples becomes flat from the vacuum really fast. On the other hand, he is a spitter with acid reflux and I don't want him to have too much and gag on it...

any advice is welcome.
Mayan
(mom to Adi 12/04/02)

[daisymommy]

Those are usaully all the signs of needing a faster flow. When you do switch to a faster nipple, your son may not be prepared for the faster flow though, and it may take a few times for him to get used to it. Every 3-4 months we go through this with Josh, to the point that he becomes so frustrated that he doesn't want to eat, even though he is hungry. Talk about lack of patience! Once we figure out he needs a faster flow, a few feedings later he is a happy camper, and will ofter increase his fluid intake.
BTW--we are using Avent bottles and Josh had reflux as well. The faster flow didn't make it any worse.