I've heard of people itching when they are exposed to hot water, like after baths. It is a common reaction though it can be a sign of a medical problem with the blood. I've never heard of that reaction with cold water. While you may be allergic to the spray, it doesn't explain why you would have a problem in just plain water, unless you are allergic to something in the water. Do you have the same reaction in different kinds of water: well water vs. city water vs. lake water vs. ocean water? There are also some little gnats and yellow flies that can cause huge hives when they bite and even severe allergic reactions. There were also some articles on the net about drugs in our water that aren't getting cleaned out by sewage treatment plants. You can google for them. Also, if you have the problems exclusively in well water, you may contact the health department about it because you might need to chlorinate your well. Also, sometimes ammonia levels are high, not high enough to affect normal people but cause problems for sick people and higher ammonia does burn and itch and might cause a similar problem. To find this out, take a sample of the water that is giving you hives in to the department of natural resources or health dept for testing, or buy an aquarium ammonia test kit and test yourself.
Could it be possible that you are allergic to a medication or food and the water is just triggering the skin reaction? In the hot tub, I think high chlorine.
An allergist might be able to skin test you and blood test you and find out exactly what you are allergic to. I know silicone can cause problems because my mom has a lot in her face from a car accident and I used to stick my hands in silicone solution every day at work when I was young. I haven't had any specifically.
I hope you figure this out and feel better.
--Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us. Bill Watterson (1958-) cartoonist "Calvin and Hobbes"
Ills--Sjogrens-Lupus-like AI Disease, Hashis, Vitiligo, spinal stenosis/fusion with plate, salivary/lymphectomies, Diabetes, NAFLD, COPD, RLS, neuropathy, trigonitis, hystero, diffuse brain atrophy, GI nightmare
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