Bitter mouth may be due to mental factors, medications, bile reflux gastritis, gallstones, etc., which can be eliminated by regulating emotions, applying medications, and surgeries according to their causes. 1. Mental factors: stress, anxiety, lack of sleep leads to nerve dysfunction, causing bitter mouth, can be adjusted by regulating emotions, releasing stress, and maintaining adequate sleep, generally can be gradually improved. 2. Drugs: Taking certain drugs, such as tetracycline, 5-fluorouracil, etc., can cause mouth bitterness, which can be gradually recovered after stopping taking the drugs. 3. Bile Reflux Gastritis (BRG): Bile reflux into the upper gastrointestinal tract can cause bitter mouth, can be given aluminum thioglycollate, misoprostol, mosapride, ursodeoxycholic acid, omeprazole and other drugs. 4. gallstones: bile stagnation can not be discharged resulting in bitter mouth, you can consider surgical removal of stones or removal of the gallbladder. Bitter mouth may also be caused by other reasons, it is recommended to consult a doctor in a timely manner to clarify the cause of the disease, and then follow the doctor’s instructions for treatment and medication, do not take medication on their own.