Before you can start treatment on this study, you will have "screening tests." These tests will help the doctor decide if you are eligible to take part in this study. Your complete medical history will be recorded, and you will have a physical exam. You will also be asked to complete 3 short questionnaires about your quality-of-life and current saliva flow. These should take about 5 minutes to complete. You will be asked to collect saliva in a vial (small tube or jar) for 5 minutes, by allowing saliva to collect in your mouth and then spitting it into the vial. You will be asked to collect saliva twice at each time point. One collection will be like it is described above. The second collection will be after you have held a sour liquid in your mouth for 1 minute. A traditional Chinese medicine diagnosis will also be conducted. This will include diagnosis by a doctor as well as by using a heart-rate machine and taking a photograph of your tongue. This will allow a more objective check of your heart rate and tongue condition.