Have you looked at things like grass? My DD cannot go onto grass without having a huge reaction. Lucky for me she hates going onto it, so always stays on the blanket, except on NY Day and so that night her eczema was really bad. Never mind, the steroid cream cleared it up very quickly. I guess I am lucky that it works on her skin most of the time.
How often do you bath him and what do you bath him in? My DD is only bathed 2 - 3 times a week otherwise her skin is terrible. And all I use is sorbolene cream, anything else just seems to set her off.
Check your washing detergent as well. I know that I do react slightly to some washing powders, so it might be that. Or is he under any stress at all? Sounds silly in a baby, but if you are getting stressed, he might be picking up on that and making his eczema worse? What about his formula? Have you changed brands or types lately and if not, have they slightly changed their ingredients? Or maybe the utensils you are using contain traces of dairy?
Lots of questions to ask yourself, but hopefully one of them might help find the cause.
Cymantha, NSW, DD 20/12/2003