Try 2.5% topical steroid cream just when the hives appear. If you let them go they will not go away. You have to get this from an MD as a prescription. I have had premenstural hives since I was 19 years old....and they are miserable. They always appear on my face. If you get the steroid cream on them right away they will go...otherwise it will take awhile. I do not believe it is an allergy. It has improved since I have been taking serotonin modulators....prozac. But I am convinced after 30 years that is you hit them the moment they appear with the high percentage steroid cream they will help them go away.