Why does bad breath persist?
Quick answer
Persistent bad breath may involve plaque, tooth or gum problems, dry mouth or other causes. If it remains after several weeks of self-care, seek assessment rather than simply masking it with mouthwash.
Details
Care and cause-finding
Clean teeth, the spaces between them and the tongue gently, and keep dentures clean if you use them. Notice links to smoking, food or dryness. Bad breath does not automatically indicate a stomach problem.
When to get checked
See a dentist for persistent odour, bleeding or swollen gums, or toothache. Dryness may also require a medicine and health review. Breath fresheners can mask odour temporarily but do not treat existing decay or gum disease.
Related question: Is tongue cleaning important?.
Note: This answer is for educational purposes and does not replace a consultation with a specialist who examines your case in person. Do not use it for self-diagnosis.