Whenever I feel vasoconstriction that is bothersome, I take a nice hot shower. Not too hot, but just enough that you totally warm up.
There are some nice vasodilators that you can have on hand for the future. L-arginine is good for it. Niacin and magnesium both dilate the blood vessels as well, as do cocoa, garlic. If you preload with L-arginine in particular, it really helps to prevent a lot of the vasoconstriction you'd normally feel.
However in general, if you're getting vasoconstriction that bad, it's probably a sign you should chill out on how much you're taking.