How do you get rid of really bad breath?

Oral hygiene: Start with good oral hygiene. Antiseptic mouth washes. If it still persists, see your dentist to have your gums/teeth evaluated. If those are fine, talk to your doctors to delve deeper into your history to see if you have any gastro intestinal or lung issues.

Dentist, brush, flos: Bad breath can have many causes. The most common source of really bad breath or halitosis is periodontal disease and/or tooth decay. You should see a dentist to determine any oral pathology and get it corrected. Brush 2 to 3 times a day, floss daily, use an antibacterial oral rinse. Another thing people tend to miss is the tongue. Brush the tongue thoroughly as far back as you can go.

Could be: Dental so see your dentist and get checked for gum disease. If you have done that consider watching your diet and brushing your tongue after brushing teeth and flossing. If none of these solve the issue then check with your md or gastroentorologist.