Rashes are also possible. I got a rash a week or so after DNP once. It was terrible. It was like poison ivy all over my body. The guys on the anabolics board said I'm not the only one. I thought I started to get another one when I woke up all itchy yesterday with swollen forearms. Luckily I was just attacked by some frikking bugs that have marked my home as their territory as of late.
Yeah the sweat will do it all the time. If i wear my body armor all day I sweat and I break out where the sweat was. Try using a stridex pad on your face or wherever before bed.