Maybe? How long has he been using the formula?

Try changing one thing at a time, though, and see how that goes. If you change all the possible things at once you'll never know which it is.

@nomaci He is cranky.. in trying Cera ve cream today . Do you think is the formula?

@lexonmars today we are trying cera ve cream and change the detergent too. Let see.

Could be heat rash, or dry skin brought on by sweating. My son gets both so easily, and it's looks like little bumps, sometimes red, usually where he presses against straps or the carseat. Do they bother him? Is he super cranky, or trying to touch it a lot? Put some lotion on...the cetaphil baby works best for my son. If it spreads or gets worse or he really seems uncomfortable, call his doctor.