Breath odor
Definition
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Breath odor is the scent of the air you breathe out of your mouth. Unpleasant, distinctive, or offensive breath odor is commonly called bad breath.
Alternative Names
Bad breath; HalitosisConsiderations
Some disorders will produce specific, characteristic odors to the breath.
A fruity odor to the breath occurs as the body attempts to get rid of excess acetone through the breathing. This is a sign of ketoacidosis, which may occur in diabetes. It is a potentially life-threatening condition.
Breath that smells like feces can occur with prolonged vomiting, especially when there is a bowel obstruction. It may also occur temporarily if a person has a tube placed through the nose or mouth to the stomach to drain the stomach contents (nasogastric tube) in place.
The breath may have an ammonia-like odor (also described as urine-like or "fishy") in people with chronic kidney failure.
Causes
If previously normal breath turns into halitosis, causes could include:
- Abscessed tooth
- Alcoholism
- Cavities
- Dentures
- Drugs
- Paraldehyde
- Triamterene and inhaled anesthetics
- Insulin - injection
- Food or beverages consumed (such as cabbage, garlic, raw onions, or coffee)
- Foreign body in the nose (usually in children)
- Often (but not always) there is a white, yellowish, or bloody discharge from one nostril
- Gum disease (gingivitis, gingivostomatitis)
- Impacted tooth
- Lung infection
- Poor dental hygiene
- Sinusitis
- Throat infection
- Tobacco smoking
- Vitamin supplements (especially in large doses)
- Acute necrotizing ulcerative gingivitis
- Acute necrotizing ulcerative mucositis
- Acute renal failure
- Bowel obstruction (can cause breath to smell like feces)
- Bronchiectasis
- Chronic renal failure (can cause breath to smell like ammonia)
- Diabetes (fruity or sweet chemical smell with ketoacidosis)
- Esophageal cancer
- Gastric carcinoma
- Gastrojejunocolic fistula (fruity-smelling breath)
- Hepatic encephalopathy
- Diabetic ketoacidosis
- Lung abscess
- Ozena, or atrophic rhinitis
- Periodontal disease
- Pharyngitis
- Zenker's diverticulum
Home Care
Use proper dental hygiene (especially flossing), and remember that mouthwashes are not effective in treating the underlying problem.
Fresh parsley or a strong mint are often effective ways to fight temporary bad breath. Avoid smoking. Otherwise, follow prescribed therapy to treat the underlying cause.
When to Contact a Medical Professional
- Breath odor persists and there is not an obvious cause (such as smoking or eating odor-causing foods).
- You have breath odor and signs of a respiratory infection, such as fever, cough, or face pain with discharge from the nose
Your doctor will take a medical history and perform a physical examination.
You may be asked the following medical history questions:
- Is there a specific odor?
- Is there a fishy smell?
- Does the breath smell like ammonia or urine?
- Does the breath smell like fruit or is there a sweet-chemical smell?
- Does the breath smell like feces?
- Does the breath smell like alcohol?
- Have you recently eaten a spicy meal, garlic, cabbage, or other "odorous" food?
- Do you take vitamin supplements?
- Do you smoke?
- Does good oral hygiene improve the odor?
- What home care measures have you tried? How effective are they?
- Is there a recent sore throat, sinus infection, tooth abscess, or other illness?
- What other symptoms do you have?
The physical examination will include a thorough examination of the mouth and the nose. A throat culture may be taken if you have a sore throat or mouth sores.
In rare cases, diagnostic tests that may be performed include:
- Blood tests to screen for diabetes or kidney failure
- Endoscopy (EGD)
- X-ray of the abdomen
- X-ray of the chest
Antibiotics may be prescribed for some conditions. For an object in the nose, the doctor will use an instrument to remove it.
Reviewed By: Michael Kapner, D.D.S., General and Cosmetic Dentistry, New Rochelle, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, M.D., MHA, Medical Director, A.D.A.M., Inc.
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