What Causes Skin Rashes On Face?

I think my roommate is doing meth. He admitted to doing it "socially" a few few times in recent weeks with his new sexual partner. I told him he would hove to move out if he didn't stop. He was out all night yesterday and today he went to the doctor for a dry skin rash on his face (he says the doctor told him it was a fungus. I can only find pics of meth SORES I am trying to find visual evidence of his meth use.