Suggest Remedy For Red Spots And Rash On Torso

My husband has broken out in a rash appearing in red spots all over his torso mostly on the front with a few on his back and neck. They appear red raised blotches with a dry white surface and are not itchy. He bathed in Dead Sea bath salts a couple of days before the rash appeared due to a bad back. He has also been using an ibuprofen gel on his lower back but the rash is predominantly on the chest and rib area.