When is gas something more? (i.e., allergy/intolerance)

mrs.gee

DS is 6w and EBF. About once a day he has a throw-down, back-arching scream-fest at the boob, usually in the late afternoon/early evening after a long nap. He will eat for 5 minutes and then start arching his back and screaming. It can last for 45 minutes or more. Usually he'll produce multiple burps and poops during this time and finally conk out, exhausted. Generally I can coax him back onto the boob at this point although sometimes he'll reject the breast he was on. He usually only feeds on one side per feeding and this doesn't happen any more or less when he's had both breasts at some point earlier in the day. Occasionally we have these fits in the early morning, which I've attributed to multiple middle-of-the-night feeds with insufficient burping (because he passes out and I'm lazy about rousing him to burp). Poops are normal (golden-colored, not green or mucousy).

Sound like normal newborn angst? We used Mylicon with DS#1 with great success (he was also EBF) but now that it's not available I'm at a bit of a loss. Gripe water isn't helping.

Tx so much for any advice.