<<Disclaimer: Verify this information before applying it to your situation.>>

Sharon,

This is not medical advice; I'm just a layperson.  It is my
understanding thirst is an indicater of diabetes, but there are other
indicators too -- frequent urination, and some others I believe.  You
might want to look into Sjogren's Syndrome.  My Dorland's Medical
dictionary gives the following definition:

Sjogren's Syndrome:  a symptom complex of unknown etiology, usually
occurring in middle-aged or older women, marked by keratoconjunctivitis
sicca, xerostomia, and enlargement of the parotid glands; it is often
associated with rheumatoid arthritis and sometimes with systemic lupus
erythematosus, scleroderma, or polymyositis.  An abnormal immune
response has been implicated.  Called also Gougerot-Nuloch-Houwer
syndrome, sicca syndrome and Sjogren's disease.

Lisa in Iowa