Sominex symptoms and conditions

has anyone ever had sudden case of Hives on their face? from taking 10mg. of Ambien for 4 weeks. Sometimes, I even just took half that. I have never had Hives from Anything before in my life......not lotions, foods, soaps, sunbathing, pools, hot tubs, medicines, back patches, prescriptions, vitamins, etc. never. I'm in my 50's. Had this four days now and after a shower seems worse. Active Ingredient in Benadryl/Sominex seems to make it a little better, but can't take that and be sleepy all day/all evening. Taking Ambien is one of only 2 new things I have done differently in the last month.