Bitter and dry mouth in the middle of the night, you can drink water, but do not drink too much water, so as not to cause an increase in nocturia affecting sleep. In the middle of the night, the mouth is bitter and dry if you go to bed before eating too salty food or water supplementation caused by insufficient, appropriate supplementation of boiled water can improve the symptoms, but pay attention not to drink too much, so as not to cause abdominal distension and discomfort and nocturnal urination increased, affecting sleep. If you often have a bitter and dry mouth at night during sleep, excluding objective factors, you need to consider the existence of high metabolic state, such as diabetes, hyperthyroidism, or the possibility of mental thirst, you need to be treated for the disease. If accompanied by excessive drinking and eating, weight loss, need to go to the hospital for further fasting blood glucose, thyroid function and aldosterone levels and other related tests to clarify the diagnosis, further treatment.