Summary
Definition
History and exam
Key diagnostic factors
- malodorous breath
- halitosis not noticed by either clinician or patient's partner/relatives
- history of obsessive behavior, depression, phobic anxiety, paranoid ideation, and reduced social interaction
- patient reports that people react to his/her bad breath by covering their nose and opening windows
- consumption of onions, garlic, or spiced food
- evidence of dental and/or periodontal disease
- evidence of disease of the oral mucosa
- evidence of nasopharyngeal disease
Other diagnostic factors
- evidence of upper respiratory tract or gastrointestinal disease
- evidence of upper respiratory tract and gastrointestinal malignancy
- evidence of endocrine, metabolic, hepatic, or renal disease
Risk factors
- oral disease
- respiratory disease
- gastrointestinal disease
- hepatic disease
- renal disease
- endocrine disease
- metabolic disease
Diagnostic investigations
Investigations to consider
- sulfide monitor
- gas chromatography
- benzol-arginine-naphthylamide (BANA) test
- dark-field microscopy
- PCR of oral bacteria
- selected ion flow tube mass spectroscopy
Treatment algorithm
Contributors
Authors

Director and Professor of Oral Medicine
UCL Eastman Dental Institute
London
UK
Disclosures
SRP declares that he has no competing interests.

Senior Clinical Lecturer in Oral Medicine
UCL Eastman Dental Institute
London
UK
Disclosures
SF has received research funding and advisory/consultancy fees from Amgen for work unrelated to this article. SF has also received fess from professional conferences for lecturing on topics unrelated to this article.
Peer reviewers
Professor of Oral Medicine
Department of Oral Sciences
University of Palermo
Palermo
Italy
Disclosures
GC declares that she has no competing interests.
Professor
Howard University College of Dentistry
Washington
DC
Disclosures
RSB declares that he has no competing interests.
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