That's not something I have ever heard of before! This probably isn't related to your particular question, but on a recent episode of 'House MD', there was a guy that was drinking a whole lot of water, and one of the doctors said that could cause him to have low sodium (lower than what is considered normal). I don't know if there's any correllation between having low sodium and being really thirsty....doesn't seem like their would be....but I felt inclined to mention it all the same! But it does bring to mind that perhaps since you are drinking alot of water, maybe you aren't getting enough of a certain vitamin/mineral...maybe its getting flushed out of your system by the water and you aren't replacing it with food or a vitamin supplement? That could be the reason for your thirst I guess! Hopefully someone else will have a better answer for you, but in the meantime....if I were you, I would probably start taking a multivitamin and see if that helps. It couldn't hurt! Good luck to you!
When you drink too much water, it causes an electrolyte imbalance... this is what happened on the episode of House. This is also why during the summer when people do anything out in the heat they need to drink something like Gatorade to replenish the electrolytes as well as fluid.
I don't know why you would wake up thirsty. Are you unusually thirsty during the day? Are you diabetic? Are you eating a lot of salt or sugar during the day? Do you take a multivitamin? Are you taking any medications that might cause thirst? Do you have problems urinating?
Any of these things could indicate a cause, but if this is something that is just starting, you should try to figure out what change you made right before you noticed (whether it is taking a new medication, eating a different food, etc etc) - something different from what you are used to. If this continues and it bothers you, you should see a doctor to make sure nothing serious is going on.
Sorry I can't be of more help to you... Certainly, you don't need more fluid, so it is important to recognize that your body might be trying to tell you something else... especially if it doesn't go away.
wow, i'm not sure where to direct you for this one... Certainly, with that amount of water intake, I would recommend taking a multivitamin if you don't already.
I take in lots of fluids in day, and I have woken up terribly thirsty at night at times, but had nothing to do with my fluid intake. I tend to be an open-mouth breather at night, and I would wake up with terribly dry, cotton mouth because of the dry air/lack of humidity. The only solution for me was to drink water right before bed and keep water at the bedside; but obviously getting back to sleep is the bigger issue for you.
Unless anyone else has any better ideas, I wouldn't worry about it unless it is interfering with your sleep to a point that you must have the problem resolved, then I would seek medical advice.
I really don't like multi-vitamins. They make me feel ill, and I hate swallowing pills. So, I think I'll just have to stick to trying to get my nutrients from somewhere else.
Hmmmm the open-mouth breathing got me thinking. Maybe a small humidifier beside the bed?
The other thing I'm wondering about is, perhaps your mouth and body have become used to having so much water that they feel "odd" going 5, 6, 7 hours at a stretch without any. Could it be you're drinking too much?
Have you tried cutting back to maybe 72 oz for a few days to see what happens?
Have you been tested for diabetes? This was the clue that my dad was diabetic. He was drinking at least 2 gallons of water a day and probably 2 liters of pop too and finally went to the doc because he couldn't quench his thirst. (His first fasting blood sugar was almost 500! )
Other than that, I've never heard of the more your drink, the thirstier you get. You might try drinking a bit less during the day and see if that helps.
Dawnyal - I suppose I better get tested for Diabetes. The only thing is that I'm not at all thirsty during the day. It's a real challenge to drink as much water as I have been. I carry around a 20 ounce bottle and remind myself ever few minutes that I better take a sip. About the only time I actually feel thirsty is while exercising (and in the middle of the night). Well, I guess I'll have to make a doctor's appointment.
Lena - I think I might get a humidifier. I wouldn't be surprised if I breathe with my mouth open, especially in this season of allergies.
Question about Water
But it does bring to mind that perhaps since you are drinking alot of water, maybe you aren't getting enough of a certain vitamin/mineral...maybe its getting flushed out of your system by the water and you aren't replacing it with food or a vitamin supplement? That could be the reason for your thirst I guess! Hopefully someone else will have a better answer for you, but in the meantime....if I were you, I would probably start taking a multivitamin and see if that helps. It couldn't hurt! 
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