It's crazy how dismissive people are. My partner had a comprehensive allergy test done, the kind where they draw a grid on your back and apply different substances in each square.

You're supposed to leave and come back a few days later but my partner had a reaction in every square before she left the doctor. They asked if the interns could come take a look because they'd never seen such a complete reaction.

Not sure if it's what you meant, but I had a similar story where I reacted to everything, even the control. The allergist took that to mean "you're really allergic to everything," but I went looking for a second opinion who was able to get both the positive and negative controls to work. Turns out I'm not allergic to everything, the first allergist just didn't recognize benign dermatographia and was a bit too quick to ignore my positive reaction to the negative control. In all, it saved me a good chunk of change and sensitization risks that would have come from having unneeded components in my allergy shots.

I don't know the details of your case or if any of this applies, but if by chance you were in the same boat wrt the negative control it might be worth circling back for a confirmation test at some point.

I'm exaggerating a little, my partner has extensive allergies but not absolute. I jokingly say my partner is allergic to life but in reality it's just life on earth.

I had this test done. Your partner needs antigen shots they really help, ask their allergist for this therapy.

I'm not soliciting for advice, my partner has been seeking medical treatment for allergies for at least 30 years.

well you never mentioned antigen shots, so thought I'd share a n=1 therapeutic that worked for me. Allergies suck, hope your partner finds relief.

Fun fact, I'm actually mildly allergic to salt. Docs didn't believe me and just tried to say it was GERD or similar. Finally found one that did some more tests and yep.

I also can't be around any strong perfumes or I'll break out in hives. It sucks when someone on a plane comes on like they just took a shower in the stuff.

Wait, what? I'm pretty sure you can't be allergic to sodium chloride. Salt is literally part of your body. You'd die if you didn't ingest any salt.

Do you mean you're allergic to some common additive in table salt, or specifically to elevated salt concentrations? The former sounds like something you could call an allergy (but not to salt itself); the latter I probably wouldn't call an allergy so much as higher sensitivity to significantly hypotonic food or drinks. An allergy is usually defined as an excessive, damaging immune reaction to a foreign substance that is itself harmless at that concentration. Salt isn't a foreign substance.

I get the feeling a lot of people are lumping tons of things into the category of "allergies" where the underlying biological processes are very different. That doesn't mean the reactions aren't real, but it makes it very difficult to reason to reason about them. When everything's an allergy, the word allergy stops having any useful meaning.

Most "plain old salt" available through commercial sources does contain several synthetic additives as "flow enhancers".

Indeed, but then it wouldn't be a salt allergy so much as an allergy to those additives (and one that you could easily fix by cooking with proper pure NaCl).

Sure, but many don't even know it's usually there, even when the ingredient list just reads "salt".

Easier said than done.

I received similar skepticism from people for coconut but after a few times of my lips turning purple they started to believe me. I seemed to have aged out of it though as more recent accidental exposures haven't resulted in a reaction.

I'm not about to tempt fate and willing subject myself to it.