Oh, we know I'm allergic to mold and mildew. I've been on allergy shots for over a year (and those are the second round, first done about 12 years ago) so we already went through that testing. But ever since I got the hives, I've stopped those shots (my decision, but when I told the allergist why, he totally agreed with me).
I've been tested twice for lupus and other auto-immune diseases, as well as a couple of other things I've since forgotten (

), but 5 doctors (the 4 I went to and my mom's cousin) all say it's a classic case of allergic reaction rather than a rash due to sickness. Lupus *is* a possibility despite the test results since my mom has it, but all the doctors think these hives are unlikely to be due to Lupus. They said rashes that itch like this are typically *not* due to a disease.
I'm already on Zyrtec and Singluair daily, have been for years. Tried the Claritin / Clarinex with absolutely no obvious improvement in symptoms. Tried zantac and tagament with no impact. Tried doxepin, another common one used, and I couldn't take it. The way it made me feel actually scared me so the dr said drop that one. I've honestly lost count of the number of different antihistamines we've tried, including atarax, and none of them helped. The one that decreased the itching the most and had the biggest impact on the hives was the benadryl, honestly with the least amount of drowsiness. Oh, don't forget the 2 different cortico-steroid creams, 2 different lotions, and benadryl cream. Oh yeah, and an antibiotic that usually works on me and as it turns out cleared up a *different* problem. LOL! But still didn't help the hives.
The only thing we *haven't* done is steroid shots. I've exhausted the options my allergist and dermatologist can come up with (other than the shots, which they said was a last resort now-a-days) other than giving it time. We've just stuck with the combo that works the best with the least side effects: benadryl and nutrogena lotion. Their new soothing-relief lotion is *great*. In the meantime, I itch anywhere from barely to HORRIBLY, I'm tired almost all the time (my MIL, who is a nurse, said she couldn't believe I'm still awake. LOL!!), I'm drinking 4x as much caffiene as I should just so I can stay awake at work, and I feel ugly on the days it hits my face. Which, thankfully, is rarely. But at least I've gotten a rhythm down to minimize my work impact, and I've registered the situation with the office nurse and my manager. I've gotten to where I pretty much just take either 2 or 4 benadryl daily, unless it's *really* bad. That's the only way I can get things done and feel like I'm not wasting my time.