There is no vaccine against the common cold.
Ah, you are right. Still there's a flu vaccine.
I'm not sure that the heated salt is hot enough to be worrisome. What ill effects do you think are likely?
I don't have specific concerns, but in general heating up a region under pain seems to be an idea that could be within standard medicine and it doesn't seem to be standard practice.
If it would be useful, why is there no big pharma company that sells a creme that heats up ears and markets it?
I've never heard of the salt/ear thing, but warm compresses are fairly standard advice for certain types of eye infections. I believe the main goal there is less to increase blood circulation and more to soften oils that might be blocking the glands in the area, though.
Physical heating is something that pharma companies aren't really equipped to monopolize, but I have seen microwavable hot/cold packs. They don't seem to offer much advantage over a warm towel.
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