Brief Answer:
Additional information needed

Detailed Answer:
Hello,

I understand your concern. Dry mouth and excessive thirst can be symptoms of many conditions, therefore more information is needed in order to get to a more accurate diagnosis.
So if you could please answer the following questions for me I may be able to better assist you.
Have you noticed a change in taste (despite the salty taste) recently? Have you been experiencing bad breath, irritated gums or thick saliva? Do you also feel like your eyes are dry or itchy? Do you urinate frequently? Has the color of your urine changed recently? Do you feel fatigued and low in energy? Have you ever experienced a head trauma? Do you have blurry vision?

I will be waiting for your answers.

Take care.

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Brief Answer:
Check blood sugar

Detailed Answer:

Although, for a more accurate diagnosis, I would need you to provide an answer for the all the questions I have asked above, based on what you refer, I am inclined to think that you might have a problem with high blood sugar. So I recommend you check this first. If Diabetes is ruled out, then I would have you test your blood ADH levels (antidiuretic hormone levels) to rule out Diabetes Insipidus, which, contrary to its name, has nothing to do with sugar levels, but rather low levels of a hormone that keeps water in the body. Diabetes Insipidus causes excessive thirst which and urination due to the body's inability to hold water.
If this is not the case, then your doctor will do a simple test for your eyes' ability to lacrimate (produce tears). This test is helpful to rule out an autoimmune disease which causes dry mouth and dry eyes.

So I recommend you see a doctor who, based on a physical exam will determine the order of the above mentioned tests to get to the right diagnosis.

I hope this helps. Please feel free to follow up with the tests results.

Take care

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