R.,
I always make my homemade "Pumpkin"pie out of acorn squash because I like the flavor better. But a sweet potato pie would be great too, and its not related to the pumpkin squash so the allergy risk would not be there.
My skin can't handle the pumpkin on it either, it gets red irritated and itchy. So I wear dish gloves to carve them.
One thing with allergies, is each time you are exposed to the food or drug it can get a little worse. So be careful how many times you let him eat it before he gets tested. It could turn in to an anaphylactic reaction eventually.
Hopefully it is just an intolerance that his body will be able to get over and handle.
Its probably the spices he likes. You could try making other treats, cookies, muffins, and just use the same spices, and he might like it just as much.
Good luck
E.
here is one web site I found, but you could do a search for it too, just to get more info.
http://www.helium.com/items/1362658-what-you-need-to-know...