Bad breath can be caused by tooth decay, gum disease, lack of saliva (xerostomia), certain foods and drinks, tobacco, medications or illness.

Treatment
Schedule a dental appointment to find out if your bad breath is being caused by tooth decay, gum disease, or a medical condition that should be treated by a physician. If you have a dental problem, your dentist will recommend a course of treatment to stop any infection, clean and restore your teeth, and improve the health of your gums. Your dentist may also recommend that you take a hard look at your daily dental hygiene. Remember, you should be brushing at least twice a day and flossing at least once daily. If your bad breath is not a dental problem, your dentist may suggest changes to your eating and drinking habits or refer you to a physician.