allergic rhinitis
"I had swollen legs and feet from what I've since discovered was a histamine reaction due to eating two foods that are high in histamine. Dark chocolate and almonds. It was suggested I take Benadryl as this helps many people with this type of reaction. I tried Benadryl first and didn't have any lessening of the swelling. The next day I tried Claritin 24 hour and within hours the swelling was gone.  If you have trouble with edema when having a histamine reaction you may want to give this a try.  I should note that I have no other allergy symptoms at all.  Only edema.  Something to do with how my Mast Cells don't work they way they should."