I have suffered from halitosis for over seven years now. I had my tonsils removed in the hope of curing the problem, to no avail. I have used all the mouthwashes one can think of, but they only provide temporary help. I have undergone a thorough medical checkup to see if I have a liver infection, but I seem to be in perfect health. Where do I go from here? I smoke two cigarettes a day and drink beer occasionally.

L.W.

Bad breath (halitosis) can have many possible causes. Tonsil problems and liver infections are not very close to the top of my list. I hope your doctor had a very good reason for thinking that your tonsils caused your halitosis, since tonsils are not usually to blame.

Halitosis is more commonly due to dental problems, such as tooth decay or gum inflammation (gingivitis), infections of the nose and sinuses (rhinosinusitis), and gastroesophageal reflux disease. You may want to scrutinize your diet, since many foods promote bad breath. (Garlic and onion are the most notorious examples.) Smoking certainly does not help your situation. Rarer causes of halitosis include cancers of the oral cavity or throat and "psychogenic halitosis" (that is, your breath bothers you but no one else).

If you do not see a dentist regularly, you should have a thorough dental examination. The next step would be to find an ear, nose and throat specialist (ENT) who can perform a careful examination of your upper airway and digestive tract. Using a flexible camera called a fiberoptic scope, an ENT can inspect your nasal cavity, throat and voice box in order to differentiate among the various diagnoses listed above. If there is some doubt as to whether you have sinusitis, a CT scan may be required to investigate this possibility.

A visit to your internist or family practitioner might also be helpful, since there are a number of medical problems that are associated with halitosis. For example, kidney and liver failure both cause characteristic breath aromas. I say that such a visit "might" also be helpful, because most such medical problems would, after seven years, have caused more symptoms than just bad breath. That's why, if I were you, I would begin my investigations with a dentist and an ENT.