This doesn't happen all the time, but when it does happen it drives me crazy. I'll go through spells of being just incredibly thirsty, but also constantly having to urinate. Those two things seem to be contradictory to each other?? When I go through these spells its bad enough that it interrupts anything I am trying to do because I am constantly having to go to the bathroom.

Those are symptoms of diabetes. Please visit your doctor for a checkup.

Being thirsty and urinating are classic symptoms of diabetes, however, you say that it doesn't happen all the time.

At what times times does it happen? Are you obese? Do you eat salty foods sometimes and drink a lot of beverage? Do you exercise and drink a lot of water?

Now, diabetes is nothing to fool around with. You should go see your physician.

I went to my doctor for it about a year ago. He thought it was diabetes too, but ruled that out with a blood test. I don't do anything recognizably different on days that this happens. No I'm not obese, and I don't really like salty foods so I don't eat a lot of them. I don't even put salt on anythig but french fries. I'm totally baffled. My doctor didn't seem too concerned about it once he ruled out diabetes, but its still a pain to deal with.

Is your thirst the result of needing fluids or an oral need? What do you drink?

Sounds like diabetes. See the doc for treatment.