I had the same exact problem last time I used Clenbuterol.
It was itchy and dry, and was driving me insane at night when I was trying to sleep.
During the particular cycle with it, my fat intake was probably a little too low, and I wasn't taking as much Flax and Fish oil. I also was taking slightly more than I have taken in the past.
I added more of the suplements back in and some nuts and a little more olive oil into my diet and it did get better.
I was putting every lotion I had on with no relief! lol.
But like what a few other ppl said maybe check your carb intake, and add some Omega 3's into you diet if you aren't already.
I also bought some aloe juice and rose water, put it in a pray bottle and kept it in my fridge. I spray down after the shower and before putting lotion on and it also really seems to help. I'd say 50% Aloe, 40% mineral water, 10% rose water. You should try it.
I feel for ya though!