Maybe you can observe if the rashes go away after a while. Or try another formula to compare if there are similar symptoms. Generally, if baby is really allergic to the formula, he will display the following:
1) Dry, itchy, flaky patches of skin (eczema) often behind the knees or in the crooks of elbows.
2) Hives
3) Swollen lips or mouth (call 995 if you see troubled breathing)
4) A red ring around the anus that doesn’t seem to respond to diaper rash remedies
5) Straining to pass gas, very fussy and irritable after eating.
http://incredibleinfant.com/infant-formula/baby-formula-allergy-symptoms/
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