What do I do if I breathed in toxic fumes?

My husband was cleaning a bath tub and mixed CLR with Clorox. It apparently created a toxic fume because he started coughing, his chest started burning and he began to feel dizzy. He decided to wait it out to see if he would feel better and for the most part he does but he now has a rash on his sides, chest and some of his back. We can’t find any information about what to do online and we don’t know if this is normal or should we go to the doctor? Any insight would be helpful, because we haven’t a clue! Thank you.