# Nitpicky question on water intoxication **URL:** \ **Category:** Factual Questions\ **Created:** [January 27, 2007, 1:46pm UTC](https://boards.straightdope.com/t/nitpicky-question-on-water-intoxication/389718 "2007-01-27T13:46:32Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Canadjun](https://avatars.discourse-cdn.com/v4/letter/c/76d3ee/32.png) [@Canadjun](https://boards.straightdope.com/u/Canadjun)\ **Post date:** [January 27, 2007, 1:46pm UTC](https://boards.straightdope.com/t/nitpicky-question-on-water-intoxication/389718/1 "2007-01-27T13:46:32Z")
This is very nitpicky I know, but several times here water intoxication has been referred to as hyponatremia. I do fully understand that your blood sodium would drop dramatically due to the dilution, but would you not also have hypokalemia (low blood potassium), hypocalcemia, and hypo-a-few-other-things? Or is it just that all the other hypos are not considered significant under the circumstances? ---
**Author:** ![garygnu](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garygnu/32/2924_2.png) [@garygnu](https://boards.straightdope.com/u/garygnu)\ **Post date:** [January 27, 2007, 2:52pm UTC](https://boards.straightdope.com/t/nitpicky-question-on-water-intoxication/389718/2 "2007-01-27T14:52:24Z")
For one thing, [water intoxication](http://en.wikipedia.org/wiki/Water_intoxication) and [Hyponatremia](http://en.wikipedia.org/wiki/Hyponatremia) are not quite the same thing. IANAD, but it appears the sodium imbalance kills before other hypo-stuff becomes an issue. ---
**Author:** ![Neur0mancer\_1](https://avatars.discourse-cdn.com/v4/letter/n/46a35a/32.png) [@Neur0mancer\_1](https://boards.straightdope.com/u/Neur0mancer_1)\ **Post date:** [January 27, 2007, 7:43pm UTC](https://boards.straightdope.com/t/nitpicky-question-on-water-intoxication/389718/3 "2007-01-27T19:43:01Z")
Hyponatremia is what kills you. See, normally, you have lots of potassium in your cells, and a little outside. OTOH, you have lots of sodium outside the cells, and little inside. If your K+ drops, it’s not hard to shift just a small amount out of the intracellular fluid compartment and re-balance it. You can run into major problems with hypokalemia, but because there is a large reserve inside the cells, it takes a lot more to drop it enough to do anything than just some water loading. If you drop your Na+ too far, this results in a shift of water into the cells (both because of simple osmosis, and because of the way cells regulate ion balance - a full explanation of this is beyond the scope of this reply - see a textbook like Kandel&Shwartz for more details). This will make the cells swell just a little. This causes major problems with neurons, which depend on finely tuned gradients of ions to maintain normal function, not to mention that the brain is contained in the skull, which does not allow any room for expansion, and thus any cellular swelling raises the intracranial pressure. Convulsions… death. In a patient with very low sodium, correcting the hyponatremia too rapidly (shooting them full of high concentration saline) can result in other problems in the brain, most notably a condition called central pontine myelinolysis. ---
**Author:** ![Canadjun](https://avatars.discourse-cdn.com/v4/letter/c/76d3ee/32.png) [@Canadjun](https://boards.straightdope.com/u/Canadjun)\ **Post date:** [January 27, 2007, 8:55pm UTC](https://boards.straightdope.com/t/nitpicky-question-on-water-intoxication/389718/4 "2007-01-27T20:55:15Z")
Cool. I had a feeling it was something like that, but my physiology knowledge has its limits (I’m a programmer with a strong casual interest in medicine and related subjects, but that casual interest only takes me so far).