Getting up with a dry mouth may be due to lack of water, or dry syndrome, diabetes, chronic pharyngitis, gastrointestinal diseases, adverse reactions to medications and other reasons. 1. Body dehydration: the body drinking less water, sweating, or dry indoor air, may cause the symptoms of getting up with a dry mouth. 2. Dry syndrome: a chronic autoimmune disease that mainly affects the salivary glands and lacrimal glands, causing symptoms such as dry mouth and dry eyes, which can be manifested as the symptom of waking up with a dry mouth. 3. Diabetes mellitus: disorders of glucose metabolism will cause metabolic abnormalities in the body, resulting in dry mouth, thirst, drinking, urination and other symptoms, so it will also be manifested as getting up with a dry mouth. 4. Chronic pharyngitis: chronic inflammation of the pharynx can cause lymphoid follicle hyperplasia in the throat wall, leading to dry mouth symptoms. 5. Digestive diseases: such as chronic gastritis, bile reflux gastritis, gastroesophageal reflux disease, etc., may also be digestive reflux, stimulate the throat to get up and dry mouth. 6. Adverse drug reactions: taking antihistamines or other drugs, may cause dry mouth and other adverse reactions, leading to get up dry mouth. Get up dry mouth, there may be other reasons, you need to go to the hospital in a timely manner to check and clarify the cause of treatment as prescribed by the doctor.