Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Dry Mouth ?
    ### Response:
    Dry mouth is the feeling that there is not enough saliva in your mouth. Everyone has a dry mouth once in a while - if they are nervous, upset or under stress. But if you have a dry mouth all or most of the time, it can be uncomfortable and can lead to serious health problems.
    