Hi
First, do not allow him to cry too much before feeds as he will take in lot of air that in turn will reduce the amount of feeds too. And to burp its not enough if you hold him straight, its better to put him on your shoulders so that his tummy lies against your body, then gently pat him on his back in between the shoulder blades till he belches out the air. It might take even half an hour.
Do not rock him or change his position unnecessarily immediately after feeds. If possible for half an hr after feeds keep him straight or upper part of body raised. This will reduce the spitting episodes.
He might not sleep properly because his feeds are inadequate or gets colicky pain.
Neopeptine is safe but drops that contain
simethicone may be of more help in your baby.
What is the weight gain after birth? If weight gain is not adequate, medicines like
domperidone should be added to reduce the
vomiting.
If feeding and burping techniques are proper, spitting episodes can be reduced to a greater extent.
Hope you find my answer useful.