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I would also strongly dissagree that Iodine topically does not induce
reaction.. in fact when I come into contact with iodine I have very
severe reactions.....  Oh and also to comment on the relieve of DH...
for me at least I find that a very hot shower then gradually turning it
into a cool shower will relieve it at least temporarily... by the time
the water feels almost too cool you will feel itch free... it's
temporary, but works well when you are in that state where the blood
starts oozing down your legs from your knees and elbows...

The shower method also would obviously help keep any secondary
infections to a minimum... meaning when you scratch these bumps you
expose them to possible infection...