Causes and Workup for Dry Mouth and Dry Eyes at Night

Common Causes

Systemic medications with anticholinergic effects, including antihistamines, diuretics, antidepressants, cardiac antiarrhythmic drugs, beta-adrenergic antagonists, and chemotherapy agents, can cause dry mouth and dry eyes, according to the American Academy of Ophthalmology 1
NSAIDs, calcium channel blockers, and lithium can contribute to xerostomia, as reported by the European Association of Urology 2
Autoimmune diseases, particularly Sjögren's syndrome, can present with the classic "sicca complex" of dry eyes and dry mouth, and other autoimmune conditions such as rheumatoid arthritis, systemic lupus erythematosus, and scleroderma may also be associated with these symptoms, according to the American College of Rheumatology 1
Endocrine disorders, including diabetes mellitus and thyroid dysfunction, can cause dry mouth and dry eyes, as noted by the European Association of Urology 2, 3
Chronic kidney disease can cause both xerostomia and xerophthalmia, according to the European Association of Urology 2

Obstructive sleep apnea and other sleep disorders can contribute to dry mouth and dry eyes at night, as reported by the European Association of Urology 2, 3
Neurological conditions, including Parkinson's disease, Bell's palsy, and trigeminal neuralgia, can cause dry mouth and dry eyes, according to the American Academy of Ophthalmology 1

A comprehensive history, including symptom assessment, associated symptoms, and sleep patterns, is essential for evaluating dry mouth and dry eyes, as recommended by the American Academy of Ophthalmology 1
A complete medication review, including over-the-counter medications and supplements, is crucial for identifying potential causes of dry mouth and dry eyes, according to the American Academy of Ophthalmology and the European Association of Urology 1, 2
Physical examination, including ocular, oral, and systemic examinations, can help identify underlying causes of dry mouth and dry eyes, as recommended by the American Academy of Ophthalmology 1
Laboratory and diagnostic testing, including blood tests and autoimmune markers, may be necessary to evaluate underlying causes of dry mouth and dry eyes, according to the European Association of Urology 2, 3

Failing to review all medications, including over-the-counter products, can lead to missed diagnoses, as noted by the European Association of Urology 2
Overlooking sleep disorders as potential contributors to nocturnal symptoms can result in inadequate treatment, according to the European Association of Urology 2, 3