What causes dry mouth, dry tongue, and dry nose?

Possible causes of dry mouth and dry nasal passages include the following: 1. Environmental factors: Seasonal changes, excessively high indoor temperatures, or overly dry air—especially during winter when heating systems are in use—can accelerate bodily fluid evaporation, leading to dry mouth and dry nasal passages. 2. Individual factors: Body constitution issues such as yin deficiency with internal heat, excessive dampness, or hyperactivity of fire due to yin deficiency may result in insufficient body fluids, thereby causing dry mouth and dry nasal passages. 3. Medical conditions: Diseases such as Sjögren's syndrome, diabetes, and hyperthyroidism can impair the secretory function of glands including salivary and lacrimal glands, resulting in dry mouth and dry nasal passages. 4. Medications: Certain drugs, such as antihypertensives and anticholinergic agents, may reduce saliva production in the mouth, leading to dry mouth. Dry mouth and dry nasal passages can arise from a variety of factors, including environmental conditions, body constitution, underlying diseases, and medication use. When experiencing these symptoms, it is advisable to increase fluid intake, adjust lifestyle habits, and seek timely medical evaluation when necessary.