What Causes Halitosis?

Patient Presentation
A 10-year-old female came to clinic with ear and facial pain for 2 days. She had seasonal allergic rhinitis symptoms beginning 5 days previously. One day ago she developed left ear pain and general pain near her eyes. Her mother also said, “Her breath stinks like a dragon.” Initially her nasal secretions were copious amounts of clear discharge, but they had changed the day before to being thick, and yellow-green. The past medical history showed several years of seasonal allergic rhinitis. The review of systems revealed no fever, but increased tearing.

The pertinent physical exam showed a school age girl in minor pain with red eyes. HEENT examination showed her eyes with palpebral redness. Her nose had thick yellow-green secretions with edematous membranes, There was positive tenderness of the maxillary sinuses, nasal secretions in the posterior pharynx and strong fetid breath. Her left ear was erythematous, bulging with distorted landmarks. Her right eye had clear fluid with air bubbles. Lungs were normal. The diagnosis of seasonal allergic rhinitis with secondary infection of the left ear and probable maxillary sinusitis was made. The patient was recommended to use her antihistamine more regularly, use oxymetazoline for 2-3 days to decrease the swelling in her nose and begin Amoxicillin for 10 days. She was to restart her nasal steroid medication after 7 days assuming improved symptoms. The family was to call if her symptoms worsened or persisted.

Halitosis or bad breath can be caused by a number of problems. The most common reason is retained food, cellular debris (epithelial cells) and bacteria (usually anaerobic) combining to cause problems in the mouth. These problems combined with decreased saliva (dehydration, mouth breathing, salivary gland disease, diabetes, chemotherapy, medications, etc.) and often poor dental hygiene are some of the most common reasons for halitosis. Other reasons can also include increased protein relative to carbohydrate in diet and the oral pH is more alkaline. The back of the tongue is the most common place for retained food and cellular debris in the mouth, but other head and neck structures also can be involved such as the tonsils, nose and sinus.

Methods to improve halitosis includes hygiene and increasing saliva production with frequent brushing and flossing of teeth, rinsing the mouth with water, and chewing sugar-free gum. Mouth rinses usually are not recommended for children. Avoidance of xerostomia, medications and certain foods can also help. Treatment of primary or secondary bacterial disease and other medical conditions is also important.

Learning Point
The differential diagnosis of halitosis includes:

  • Mouth
    • Cavities and dental abscess
    • Dental appliances – teeth retainers, dentures
    • Gum disease – Necrotizing gingivitis (Vincent’s disease or Trench mouth)
    • Mouth breathing
    • Mucositis
    • Plaque
    • Diphtheria
    • Oral candidiasis
    • Streptococcal pharyngitis
    • Tonsilloliths
  • Nose
    • Atrophic rhinitis
    • Rhinorrhea
    • Infection
    • Foreign body
  • Sinus
    • Infection
  • GI tract
    • Bowel obstruction or prolonged emesis
    • Gastroesophageal reflux disease – stomach acid
    • Liver failure
  • Renal disease
    • Kidney failure
  • Pulmonary disease
    • Lung abscess
    • Bronchiectesis
  • Drugs
    • Alcohol
    • Inhaled anesthetics
    • Bismuth
    • Iodides
    • Paraldehyde
    • Tobacco
    • Vitamin supplements
  • Medications that cause xerostomia such as antihistamines
  • Medications that cause fungus such as chemotherapy, corticosteroids
  • Food (often because of the oil in the food) is absorbed and then emitted through the lungs)
    • Brassicas – cabbage, brussel sprouts
    • Cheese
    • Coffee/tea
    • Garlic
    • Onions
    • Orange juice
    • Spices
  • Other
    • Cancer – oral, esophageal, gastric
    • Diabetes
    • Head and neck structural disorders, ex. cleft palate which may allow ideal environments for bacteria to multiply without being disturbed
    • Menstruation (associated with transient gingivitis)
    • Psychological – pseudohalitosis or halitophobia

Halitosis by smell

  • Ammonia – kidney failure
  • Foul, putrid, sulfur – infections and/or debris, hepatic failure
  • Fecal – Bowel obstruction or prolonged emesis
  • Sweet – oral candidiasis, diabetes

Questions for Further Discussion
1. What other suggestions for eliminating halitosis do you have?
2. What are indications for referral to a dentist?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Dental Health and Mouth Disorders.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Illingworth RS. Common Symptoms of Disease in Children. Blackwell Scientific Publications: Oxford. 1988:170.

Halitosis. FamilyDoctor.org.
Available from the Internet at http://familydoctor.org/familydoctor/en/diseases-conditions/halitosis.printerview.all.html (rev. 9/10, cited 4/18/2012).

MedlinePlus. Bad Breath. National Library of Medicine
Available from the Internet at http://www.nlm.nih.gov/medlineplus/ency/article/003058.htm (rev. 3/21/2012, cited 4/18/12).

ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effectively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients’ is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.


    Donna M. D’Alessandro, MD
    Professor of Pediatrics, University of Iowa Children’s Hospital