Aveeno is not made from oats. Aveeno claims that there are "Active Naturals" in their products. These "Active Naturals" could be derived from soy, oats, feverfew, shiitake mushrooms, and a few other herbs. Remember that body care products are not bound by rigid rules or laws like other industries. Labels or claims mean very little. The companies making these products can make any claim and slap it on their packaging and sell it to you. There is very little regulation regarding what goes into these products, and often even less testing done prior to marketing the products. Here is an informative read:
Premium Body Care | WholeFoodsMarket.com (I know... it's a Whole Foods Market article, and people love to snub Whole Foods... but it does have some great info within it.)
If you are allergic to mushrooms, don't use Aveeno products. We learned this the hard way with our youngest son, who ended up in ER on Xmas Eve due to using Aveeno so I feel I should warn other parents out there, as well as other people thinking of trying Aveeno products. Aveeno was recommended to us by our previous dermatologist, she claimed it was a very good and gentle product and good for people with sensitive skin and allergies. I'm also allergic to lavender, and so I cannot use Aveeno products because they also contain ingredients derived from the lavender plant. Aveeno makes me break out in a horrible rash.
I'm glad it works for other people, lucky people!
But I just needed to share our experiences with Aveeno because they were pretty scary. And I keep hearing it said so often that it's such a good product, so safe, etc. Not for everybody, I guess.
I think for something like eczema you really need to find the most gentle, pure ingredients you can possibly find to use for your skin. Try to stay away from fragrances, colorings, and even essential oils or herbs or additives that do little but add a dubious claim to the product. Finding a good dermatologist who really knows what they're talking about is helpful, too.