What you have sounds like urticaria, or hives--that which you are calling whelps. So far it sounds like you have had antihistamines and steroid. As well as epinephrine. Without adequate result.
This would make this resistant urticaria.
Two drugs used with anti-histamines for resistant urticaria are dapsone and cochicine. Neither of these drugs is a steroid and many primary care or ER docs might not think to use them in this situation. A recent study published in Jan 2010 showed that most patients in this situation responded well to antihistamines and colchicine. Of course, this was in a study done by dermatologists---skin doctors. If you can get into a dermatologist, you probably will get the correct treatment. In addition, the dermatologist would probably take a sample of one of the welts so define it better under the microscope and perhaps improve your treatment in that manner.
If you have any severe systemic symptoms, such as shortness of breath, high fever, etc. then don't wait and return to emergent care.
Good luck and please let me know how this turns out.
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