BAD BREATH
Definition
Breath odor is unpleasant, distinctive, or offensive.
Considerations
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 characteristic sign of ketoacidosis (such as diabetic ketoacidosis), a potentially life-threatening condition.
A fecal odor to the breath (the breath smells like feces) can occur with prolonged vomiting, especially when there is a bowel obstruction. It can also occur temporarily if the person has a nasogastric tube in place (a tube placed through the nose or mouth to the stomach to drain the stomach contents).
The breath may have an ammonia-like odor (also described as urine-like or "fishy") in people with chronic kidney failure.
Common causes
If previously normal breath turns into halitosis, causes could include: Food or beverages consumed (such as cabbage, garlic, raw onions, or coffee)
Vitamin supplements (especially in large doses)
Poor dental hygiene
Dentures
Cavities
Tobacco smoking
Alcoholism
Throat infection
Sinusitis
Lung infection
Gum disease (gingivitis, gingivostomatitis)
Abscessed tooth
Impacted tooth
Foreign body in the nose (in children)
Often (but not always) there is a white, yellowish, or bloody discharge from one nostril Drugs
Paraldehyde
Triamterene and inhaled anesthetics
Insulin - injection
Diseases that may be associated with breath odor (not presented in order of likelihood -- some are extremely unlikely):
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