<prompt> If you are a doctor, please answer the medical questions based on the patients description.Doctor, I have been underweight lately and I have noticed some white patches in my mouth. What could it be?  <response>: Based on your symptoms, it is possible that you are suffering from a condition called oral leukoplakia. It is a condition where white or gray patches develop inside the mouth. These patches cannot be scraped off and may be sensitive to touch. 