Nighttime thirst may be caused by higher nighttime temperatures, consuming saltier foods before bedtime, rhinitis, diabetes, dry syndrome and other factors. 1. Higher nighttime temperatures: Higher indoor temperatures during nighttime sleep can make people feel hot and sweaty, leading to a lack of water in the human body, thus causing thirst. 2. Eating salty food before going to bed: Eating salty food causes the body to consume more salt, the osmotic pressure of the fluid inside and outside the cell is not balanced, the water in the cell will flow out, the cells are missing water and thus cause the symptoms of thirst. 3. Rhinitis: rhinitis patients may slightly open their mouths to assist breathing at night, the gas into the mouth is easy to make the mouth produce a dry feeling, leading to the human body to appear thirsty. 4. Diabetes: diabetic patients with high blood sugar, prone to urinate more often, the patient’s body to lose more water and thus thirst. 5. Dry Syndrome: Dry Syndrome is mainly manifested by the dysfunction of salivary glands, lacrimal glands and other organs’ secretion, which can’t normally secrete saliva and tears, resulting in the symptoms of dry mouth and dry eyes. It is suggested that patients should have a light diet, try not to eat spicy, greasy and salty food before going to bed at night, and drink water in moderation to replenish water. If necessary, patients should go to the hospital for relevant examinations to clarify the cause of the disease and follow the doctor’s instructions for treatment.