I’ve had this same experience. We went through 3 different formula brands before we found one that worked well for baby. One made her projectile vomit, one made her stomach gurgle so bad and one she straight up would refuse everytime. It’s a process, but you’ll find one that works for him!
What size teat are you using? My little one is 4 months and we still use a size 0 teat as a size 1 for as making her sick as it was too fast and not mimicking the breast. Like you she is EBF but she has one bottle of expressed milk a day but recently I’ve been combining formula and breast to get her used to it
It is not common, but sounds like a milk allergy. You need to speak to your GP. Due to the age of your baby, take him to A&E or call to 111 but don't give him formula again.
My son has a milk allergy. He would projectile vomit any time he’d have some. We went to the doctors and they suggested putting him on soya milk. He’s been fine since. Took a while for him to adjust to soya milk as it’s a little different in taste
My daughter done this I had to put infacol in her formula bottle to help her tummy digest the formula when I wanted to stop breastfeeding. Did it for a week every bottle then stopped and her stomach accepted it on its own.
This was advice from a doctor as well ☺️ it’s not the formula it’s her tummy not use to the formula. I went to a&e for it because she was bad with the projectile vomiting too.
Are you pace feeding? He could be drinking it too fast