Bad breath should first go to the hospital to check and find out the cause of bad breath, and then to treat the symptoms. Severe bad breath is generally caused by gingivitis or periodontitis, if it is gingivitis caused by bad breath, you can drink Niuhuang detoxification tablets, bacterial infection is serious, you can take oral metronidazole, if it has developed to periodontitis, you need to go to a regular hospital special treatment, through professional equipment to clean and eliminate plaque, calculus, and can be combined with oral roxithromycin, amoxicillin and other antibiotics. At the same time drink more water, you can drink honeysuckle tea, green tea, etc., can assist both anti-inflammatory sterilization, in addition to green tea has deodorant effect, can prevent bad breath. Bad breath may also be related to stomach fire, you can take oral Huo Xiang Qing stomach capsule and some other drugs to reduce stomach fire, pay attention to drink more water, rest on time.