Bitter mouth and dry mouth in the morning may be caused by gallbladder stones, bile reflux, dental stones and other reasons. 1. Gallbladder stones: Some patients with gallbladder stones may have bitter and dry mouth after the stones block the gallbladder duct, causing bile to flow backward into the stomach and then reflux into the mouth. 2. Bile reflux: This is usually caused by the dysfunction of the pylorus of the stomach and the dysfunction of the pyloric sphincter, resulting in the reflux of bile, which will lead to symptoms such as bitter and dry mouth in the morning. 3. Dental calculus: It refers to the plaque and soft scale that is calcifying or has been calcified and deposited on the surface of teeth or restorations. When the surface of dental calculus is covered with a large amount of plaque, symptoms such as bitter and dry mouth in the morning may occur. Bitter mouth and dry mouth in the morning may also be seen in dental plaque, enteritis and other diseases, if the symptoms of bitter mouth and dry mouth in the morning, persistent and unrelieved, you need to seek medical treatment in a timely manner, you can reduce the adverse effects of the disease through early detection, early diagnosis and early treatment.