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Salt and wounds

  1. Feb 13, 2004 #1
    Why does the wound hurt more if you pour salt (NaCl) on it? Does it have something to do with osmosis?
  2. jcsd
  3. Feb 13, 2004 #2
    Guess - the NaCl would dissociate and the ions would cause the pain.

    Unless of course you were a slug and then you hypertonic solution would suck all of the fluid out of your body and you would die.

  4. Feb 13, 2004 #3
    but how? does Na+ or cl- ions react with nerves better than other substances or what
  5. Feb 14, 2004 #4
    Too much of Na+ is not good. It will cause a hypertonic solution which will damgage the cell.

    But Like I said I am not sure if this is what causes the pain, it was just a guess.

  6. Feb 14, 2004 #5


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    I kinda agree with the slug idea - the reason you don't die if you touch salt, is that you are bigger than a slug, and you have an impermeable layer - the skin. With a wound, you lose the layer, and so in bodily fluids can make water leave your cells by osmosis. The damage would probably register as pain.
  7. Feb 20, 2004 #6
    The Na+ and Cl-, if it somehow is absorbed into a nerve cell at different rates, would cause electrical imbalances which could push it over the threashold and cause them to fire - hence pain.

    Half guessing.. half braining.
  8. May 20, 2011 #7
    I'm gonna agree with Jikx.

    K+ and Na+ ions are both involved in nerve impulses. To begin a nerve impulse, the stimuli triggers a release of Na+ ions into the axon, which causes a chain reaction of Na+ being pumped in all through the nerve. Pain is a construct of our brains to interpret some nerve impulses. I'm guessing that this particular nerve impulse is the same as pain.

    Though, like Jikx, I'm pretty much making an educated guess.
  9. May 20, 2011 #8


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    Gold Member

    Wow! Is there a competition to see who can resurrect the oldest thread? ;-)
  10. May 20, 2011 #9
    If you put salt on a necropost, will it hurt?
  11. May 20, 2011 #10


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    Staff: Mentor

    Yes. Mentors.
  12. May 20, 2011 #11
    I cannot see dates on PF mobile.
    Anyways it's not that hard considering you always have the link to the last page on the thread list.
    Last edited: May 21, 2011
  13. May 22, 2011 #12
    I just happened to Google: "Why does salt in a wound cause pain" or something to that extent.
  14. May 25, 2011 #13
    I agree with Jikx, but there may be more to it than a nerve firing, as sodium would indeed upset the osmotic pressure in cells, which they wouldn't like one bit. I think this may be why even choanoflagellates seem to have sodium channels (or at least the genes for them), even though said single cell animals obviously don'y have their own neurons!:
    http://www.physorg.com/news/2011-05-sodium-channels-evolved-animals-nervous.html" [Broken]
    Last edited by a moderator: May 5, 2017
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