Xerostomia

Abnormal oral dryness due to decreased or absent salivary gland secretion, predisposing to mucosal discomfort, dysphagia, dysgeusia, dental caries, and oral infections. Possible causes are medications (antihistamines, antidepressants, antihypertensive, pain relievers), cancer treatment (radiotherapy, chemotherapy), Sjögren's syndrome, dehydration, salivary nerve damage (trauma, surgery), mouth breathing (nasal congestion, sleep apnea), and lifestyle factors (smoking, alcohol, aging).