Dry mouth is termed xerostomia. The causes can be;
1) fever raised body temperature, but usually this is perceptible.
3) anticholinergic drugs,
4) Mikulicz disease (leukemia infiltrates in salivary glands),
5) Sjögren syndrome; when salivary gland are affected by autoimmune disease,
6) antidepressants and other drugs
7) parotid gland infection (parotitis / mumps)
Excessive thirst can be caused by following also (this may or may not accompany dry mouth);
1) Diabetes Mellitus
2) Diabetes insipidus
3) Medication like anticholinergics, demeclocycline, diuretics, phenothiazines
5) Psychogenic polydipsia.
Few causes need to be first investigated as your annual check ups had been normal;
b) Salivary gland evaluation.
c) Low thyroid.
Nothing serious is anticipated by this symptoms.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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