How to treat bad breath?

Patient's question:

Medical History Description
Morning symptoms: bitter taste in mouth, halitosis (halitosis has always been present; the bitter taste in the mouth is only felt in the morning after waking up well:?):

Doctor's answer:

Hello, how long has this situation recurred again? Besides these cases, are there any other discomforts? For example, swollen and painful gums that easily peel, yellow and dark urine, red tongue with yellow coating, and so on? If there are, it is likely caused by excessive stomach fire. You can take Huanglian Shangqing Wan to see if it helps.
In addition, during the treatment of bad breath, it is crucial for the patient to not only receive immediate treatment but also maintain a good dietary condition and psychological state. The patient must always stay in a pleasant mood and eat appropriately to avoid unnecessary impacts on the complete recovery of bad breath.