Bad Breath: Causes Beyond Brushing and When a Medical Visit Helps

What it involves

MedlinePlus defines breath odor as the scent of the air you breathe out of your mouth, with unpleasant odor commonly called bad breath. The medical term is halitosis. It says bad breath is usually related to poor dental hygiene.

Who this is for

• Patients whose breath stays unpleasant despite regular brushing and flossing
• Patients with a dry mouth, sore throat, sinus symptoms or a bad taste that will not go away
• Patients who notice an unusual odor, such as fruity, fishy or ammonia-like breath
• Patients who want a medical cause ruled out before seeing a dentist

What to expect

• Questions about the odor, your diet, vitamins and smoking and what you have tried at home
• An exam of the mouth and nose, and a throat culture if you have a sore throat or mouth sores
• Blood tests only in rare cases, to check for diabetes or kidney problems, since the practice lists blood work among its services
• A plan that may include treating an infection, a referral to a dentist or further testing

Why it usually starts in the mouth

MedlinePlus explains that when you do not brush and floss regularly, bacteria in the mouth release sulfur compounds, and those compounds are what you smell. Dental causes it lists include cavities, an abscessed tooth, an impacted tooth, gum disease, dentures that are not cleaned and recent gum surgery. For that reason, the encyclopedia's first home-care advice is proper dental hygiene, especially flossing, and it points out that mouthwashes do not treat the underlying problem. A dentist is often the first stop.

Food, habits and a dry mouth

Some foods, such as cabbage, garlic and raw onions, cause temporary breath odor. MedlinePlus also lists coffee, a poorly balanced diet, tobacco smoking, alcohol use disorder and large doses of vitamin supplements. A dry mouth is a frequent contributor because saliva washes bacteria away, and the dry mouth guide explains causes and relief. Fresh parsley or a strong mint can fight temporary odor, according to the encyclopedia, and avoiding smoking helps; the quitting smoking guide explains how a provider can support that.

When the source is the nose or throat

Not every case starts in the mouth. MedlinePlus lists a sinus infection, a throat infection, pharyngitis and tonsils with deep crypts and sulfur granules, and in children an object stuck in the nose, which often causes discharge from one nostril. The sinus infection guide and the sore throat guide explain two of those. Breath odor together with signs of a respiratory infection, such as fever, cough or facial pain with nasal discharge, is a reason to contact a provider.

When the smell hints at something else

MedlinePlus says some disorders produce distinct odors. A fruity smell can be a sign of ketoacidosis in people with diabetes, a potentially life-threatening condition. Breath that smells like feces may follow prolonged vomiting, especially with a bowel obstruction. An ammonia-like, urine-like or fishy odor can occur in chronic kidney failure. Conditions such as acid reflux, lung infections and liver disease are also on its list. These are uncommon, but the diabetes and kidney links are why blood tests are sometimes ordered, as the kidney function tests guide describes.

What a visit covers

The provider takes a medical history and performs a physical exam that includes a thorough inspection of the mouth and nose. MedlinePlus lists questions such as whether the odor has a particular quality, whether you recently ate odorous foods, whether you take vitamin supplements or smoke, what home care you have tried and whether you have had a sore throat, sinus infection or tooth abscess. A throat culture may be taken for a sore throat or mouth sores. Rarely, blood tests, an upper GI endoscopy or x-rays are used; the endoscopy and x-rays are referrals.

When to be seen

MedlinePlus says to contact your provider if breath odor does not go away and there is no obvious cause, such as smoking or odorous food, or if you have breath odor with signs of a respiratory infection. Antibiotics may be prescribed for certain infections. Persistent odor with excessive thirst, frequent urination, nausea or confusion is different and may need prompt care, and the excessive thirst guide explains the blood sugar link. Otherwise, regular dental checkups remain the best way to catch tooth and gum causes early.

Sources

• MedlinePlus — Breath odor
• MedlinePlus — Bad Breath (health topic)