H. pylori itself has nothing to do with bad breath, but mainly causes bad breath because its infection causes digestive symptoms.
Infection with H. pylori causes severe gastritis and gastric ulcers, and the ulcers emit a foul odor. Moreover, the bacteria accumulate in large quantities and cause food fermentation, which will also result in bad odor. If the patient pays attention to oral hygiene and brushes his/her teeth diligently, when the amount of infected bacteria is small and he/she has good living habits, or when the eradication of Helicobacter pylori is carried out at an early stage, this type of patient will not have bad breath.
When patients are infected with H. pylori, they must eradicate H. pylori, and usually choose quadruple drugs for eradication, including two antibiotics, a bismuth agent, and a gastric mucosa protector, such as omeprazole, clarithromycin, metronidazole, and bismuth potassium citrate. The medication should be taken under the guidance of a physician.