Waking up with a dry and bitter mouth may be a normal physiological phenomenon, or it may be caused by frequent smoking, liver and gallbladder diseases. 1. Physiological phenomenon: If you drink less water, or sleep in a dry environment, it will lead to the phenomenon of waking up with a dry mouth and bitter mouth. This situation can be relieved by drinking more water. 2. Frequent smoking: frequent smokers, due to the stimulation of harmful substances in cigarettes, the mouth will remain sticky for a long time, sometimes waking up with a dry mouth and bitter mouth. 3. Liver and gallbladder diseases: If you often wake up with a dry mouth, you need to consider that it may be caused by certain liver and gallbladder diseases, such as cholecystitis, chronic hepatitis, etc., these diseases will lead to a certain degree of bile stagnation, reflux, waking up with a dry mouth symptoms. Waking up with a dry mouth may also be caused by other diseases, it is recommended to consult a doctor in time to find out the cause of the treatment as prescribed by the doctor.