...You need to bring moisture back to your skin. This is what the keratosis pilaris is telling you; and is part of what the eczema has been trying to tell you. In addition, the eczema is saying that you need to restore balance (through nutrition/cleansing) to your immune system; and that you need to remove the toxins that are affecting your immune health.
Regarding the urea creams, I wouldn't personally use this option as my first choice. Here are some reasons why. Nitrogen, which is a waste product of protein metabolism in humans, is removed from the blood and converted to urea. Urea is transferred into the urine and removed from the body. Medically it is used in creams, supposedly, to restore moisture. Vitamin E oil, borage oil, and a host of other natural herbs/vitamins/oils restore moisture to the skin; therefore, why use a toxic waste byproduct to do the job. In addition, most of the prescribed creams that contain urea (although it is found in natural products as well) also contain other harmful ingredient that's not particularly good for the skin. I'm making the assumption that if you were prescribed a urea cream, that it wasn't a natural product; but rather a medication containing other harsh ingredient.
Here are several natural skin care options to consider:
Elicina cream - http://bioskincare.com/keratosis-pilaris.htm
Rose Hip oil
Burt's Bees Exfoliating soap/Burt's Bees Carrot Nutritive lotion
Burt's Bees Vitamin E bath oil
Borage Skin Therapy lotion by Shikai/Shikai's Moisturizing bath & shower gel
You can even go beyond this list of recommendations to search out other natural skin care options. If you are a resident of the U.S., a visit to your local Whole Foods market will provide you with a multitude of other options along with a few of the ones mentioned above.
In addition, I also want you to take a look at the wholehealthmd.com website to familiarize yourself with the foods that provide the vitamins/minerals/protein for which you are deficient. Start implementing these foods into your daily diet (avoiding those things for which you are allergic of course) to restore your immune health. If you haven't already, you should also consider a cleanse/detox to rid the toxins from your system. You can check out the allnaturalcleanse.com website to examine (for yourself) the cleansing system they offer. And finally, you will need to rid your environment of the allergen/irritants (apart from food) that would cause your eczema irritation. Chlorine/fluoride in treated water systems, pet dander/molds/mildew/dust mites in the air and fabric in your home, Amalgam
fillings in teeth, fluoride in toothpaste, harsh detergents/soaps/cleansers, and so forth.
Any further questions, feel free to ask.