T.
S.,
It is probably the milk. Eczema is a sign of allergic reaction and it is unlikely your baby would outgrow it in just a few months. My now 18 month old is intolerant to dairy and allergic to soy proteins. I nursed him until he way 17 months old and I had to be completely dairy and soy free the entire time (even hidden dairy and soy) or he'd get sick. He self weaned right around 17/18 months so now I can eat wha I want but he's still dairy and soy free. I know he got something he shouldn't have at daycare last week (that had soy protein in it) because he's covered in a head to toe rash right now. Soy is hidden in so many foods, it is tough to avoid especially now that he's big enough to sneak food from the other kids.
Once I cut dairy and soy out of my diet and it all cleared my system and his, my baby actually would have a violent reaction any time I'd get even a little dairy or soy. Once he'd actually felt good, when he would get something to make him feel bad, it would be spectacular.
So I think the answer is you need to cut the milk out again. Believe me, I went a year and a half with no dairy and no soy. And that included 2 Thanksgivings and 2 Christmases. It was a pain in the butt but really preferable to a miserable, sick baby.
Oh, and if anyone tries to tell you that your baby is lactose intolerant, don't believe them. There is way more lactose in breastmilk than in cow's milk and the lactose in cow's milk won't pass through your breastmilk. The problem is a DAIRY PROTEIN ALLERGY. The dairy proteins can easily pass to your baby through your breastmilk and dairy causes something like 75% of colic cases in breastfed babies. It is not an uncommon problem at all. Some babies outgrow it (my pediatric GI doctor said most babies outgrow it by 18 months or even as long as 3 years... my babe is 19 months and counting and still allergic).
Also, there are difference between an intolerance (in my son, dairy causes gas, bloating, stomach ache, screaming) and an allergy (in my son hives, screaming, eczema). They are both immune responses but the mechanism is different. But all that means to you is that whether your son is intolerant or allergic, it obviously isn't doing him any good. Intolerances are usually not fatal unless they are ignored for a long time and result in something like failure to thrive or malnutrition (they can really rough up the intestines and make it hard for a baby to digest nutrients and can also cause intestinal bleeding), but some food allergies can cause anaphalatic shock (inability to breathe) and death. Nothing to fool with. So if your think your baby has a food intolerance or food allergy, I would not ignore it.
:-)T.