Hello Everyone!

My little 4 month old has had reflux since the day he was born, he's what they call a 'Happy Chucker', although it's still just as hard. Even though he's putting on weight, he doesn't sleep properly (Cat naps during the day, wakes several times at night) and gets distressed after feeding. I've been on all available medications, nothing worked - so it musn't be acid reflux.
I was advised by the doctor to use Naan HA as it's gentler on the tummy, and have started using Karicare food thickener once or twice a day. I've noticed a huge difference in the amount of vomits, but now he poo's almost after every feed, it's starting to get quite watery and yellow.
What I want to know is - has anyone else had the same experience with thickeners? Is this normal, or is it a reaction to the product?
I can keep my baby upright the entire time between feeds and he still spits up!
Any other tips or hints for a refluxy baby?