I have had recurring hives for ten years. Usually just at night, or when I'm very tired. Usually only on my limbs, but have recently spread to my upper back. I've been to a few doctors over the years. My hives began sporadically, but over the years have become a regular nightly event. They get so bad I want to rip the skin off my body. Sometimes they get so bad, I have felt suicidal. My only allergy is sulfa. I have lived with animals and dust all my life and have no allergies to them. My local allergist insisted that if I took one of my prescribed 25mg hydroxyz every night for 6 months I would be cured. That didn't work, so he said to try it for a year. He said it would trick ,or reset my brain into not having this disorder. I hated taking it as it made me extremely groggy all the next day. So I slept every night with cold packs wrapped around my arms & legs, and only when the hives were extremely unbearable would I take the Hydroxyz. I live in MN, so recently I went to the Mayo. They call this an autoimmune disorder. They have different plans, with different drugs. They say the chance of my brain reset is a possibility, but not a guarantee. I will be starting today with a 6 week trial of taking singular & allegra. If it works they will keep me on it for?? and then begin to taper slowly off it to see if my brain has reset. They said I could continue to take Hydoxyz as needed for extreme situations. They said the combination of these two particular drugs have been pretty successful. I'm very hopeful and eager to get results. Interesting note, around the same my hives began, I was diagnosed with narcolepsy. I asked my Allergist at the Mayo, he said "they know of no known correlation".