Was it a commercially made cake? If not, then you could check the maker and look at some of her ingredients. Commercially made ones can have lots of stuff in them that are not legally required to be put on the label.
Sure hope that you get better soon. Have you tried using a spray bottle and putting a fine mist on your skin?
Oatmeal? That's not such a common allergenic. Look up some of the oat family, you may find that you have eaten some of its relatives. And you may be allergic to one or more of several other foods. I googled this, thought I'd seen it some time ago.
One of my daughters was born allergic to wheat and milk, and those two things were often attached to many, many other foods that did not have them on the labels.
Blessings...
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THIS CAME FROM THE INTERNET
Oat Allergy | OatAllergy.com
Sep 14, 2008 ... I have a daughter who is allergic to oats and a son who has a food intolerance to oats. We are currently running out of breakfast ideas for ...
oatallergy.wordpress.com/category/oat-allergy/ - Similar
Oats in Frozen Whitecastle Burgers—Any Other Odd Places You Know Of?
Posted on September 14, 2008 by Adam Darowski| 5 Comments
I’ve resorted to really only posting to this blog when content comes in from readers, and today is a good example. Reader Shauna wanted to share one of many foods that contains oats that you really wouldn’t expect to:
Sometimes there are oats found in foods you’d never expect. Frozen Whitecastle burgers contain oat fiber. Thankfully I never eat them because of the fat content, so no near fatal reactions, but I thought I would let your readers know.