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Bad breath
Medical expert of the article
Last reviewed: 07.07.2025
Halitosis is an unpleasant odor from the mouth that is felt in the exhaled air (actually "halitosis") or independently of the act of breathing.
Variants of halitosis:
- bacterial halitosis;
- exogenous halitosis;
- pseudohalitosis (psychogenic);
- symptomatic halitosis.
Bacterial halitosis is associated with the metabolic activity of oral bacteria. It is most often associated with prolonged fasting (insufficient cleaning of the tongue from plaque), rare and irregular food intake (especially soft food), as well as poor oral hygiene, dry mouth of various origins.
Exogenous halitosis is usually associated with the consumption of certain foods (garlic, onions, marinades, sauces, etc.), tobacco and alcohol.
Pseudohalitosis or psychogenic halitosis is observed in patients convinced of the presence of a serious disease. Usually there is no bad breath. However, patients are depressed and avoid communication. Most often, this pathopsychological phenomenon is caused by the consolidation in the consciousness of an anxious and suspicious personality of the idea of what was previously and was noted by others from the mouth and the development of obsessive-compulsive neurosis. Pseudohalitosis can be the debut of a neurotic form of schizophrenia.
Symptomatic halitosis occurs in diseases of the teeth and gums, nasopharynx, esophagus, pyloric stenosis, intestinal obstruction, lung diseases, endotoxicosis and poisoning.