Started as a skin rash now broken out?

A couple of days ago, my husband started complaining that he was turning red all over and really itchy. Well, now he has broken out with little zits all over especially on his chest. Any ideas of what this might be?|||could be a gazillion things--poison ivy, poison oak, sumac, psychoris, scabies, plain old allergic reaction. he needs to go to the dr.|||It could be an allergic reaction to something.