I'm sad to say I cannot offer much advice.... Though I do have some.
I've been suffering for over 5 years with CU, and have tried just about everything when it comes to trying different remedies to try ans prevent the hives from occuring when my body/skin temperature rises.
So here are things that might help:
1.) I would NOT take antihistimes more than once to see if it helps which i doubt it will. My allergist put my on them everyday, (benadryl, allegra, zyrtec, etc.) and I became allergic to antihistamines now!!! I know!! And I do not suffer from any other allergies so I'm not sure why this happened. But everyone's body is different, so just be cautious to that.
2.) No over the counter anti itch creams worked at all and believe me I tried them all bc the itching is UNBEARABLE!!!
-What I found that worked (as good as it can) are gels like Bengay or Icy pain relievers, I believe they have menthol and/or litocain in them. Not sure, just make sure you get something that makes your skin icy cold from the gel. DO NOT PUT ANYTHING HOT ON YOUR SKIN! And for me, it usually decreases the hives a lot faster and reduces itching after 2 or three applications. And also, it does not have to be as cold as ice, for me that is too cold. Just a cool cloth should do the trick if you hold it there for 15 min or so.
What to Do when You Break Out:
3.) Try to immediately cover your skin with some form of cooling it down. A cool shower, a swim, cold cloths/compresses, or a icy pain reliever gel like Bengay or other brands.(IcyHot tends to make your skin hot after it cools it, so be aware of these dangers.) And in cooling down your skin, it usually eases the pain and the hives usually go away much faster than normal. And if you apply cooling gel and it starts to itch, try not to scratch, just apply another coat of the icy gel.
From my experience, without using a cooling down method when I break out in my hives, then the hives last anywhere from a day to 3 days to even a week sometimes! But cooling down my skin, they only last anywhere from hours to one day.
I hope this helps. I've also heard of people wearing vests with ice packs in them to stay cool, among other things of that sort. But I think bc of my Fibromyalgia, the cold makes me feel as if it is the worst torture ever!
Renember, if you have found anything that works for you, I would love to hear about it! Just click CONTACT to send me an email. Thanks!