(The notes below are a summary of an article I clipped from one of the medical newspapers many years ago, which is apparently an extract from Practical General Practice 2006. The reference given is Scully C et al, What to do about halitosis, BMJ 1994; 308: 217 – 8. So it may not be the most up-to-date of resources. Still, I thought it was worth making some notes to give me a starting point if a patient presents with this problem.)
Approx 90% of halitosis is due to bacterial putrefaction in the mouth, so the first steps are:
- Encourage mouth hygiene (in stubborn cases, it’s worth a trial of 2/52 toothbrushing and flossing after every meal and using antiseptic mouthwash twice daily. However, this shouldn’t be done for longer than two weeks as it risks causing thrush.)
- Treat local infection (gingivitis, tonsillitis, sinusitis – even bronchiectasis) and advise a dental check even if nothing is obvious.
- Give smoking cessation advice if needed
- If the tongue looks furry, try scrubbing it with a toothbrush (smoking cessation may also help a furry tongue)
- Check for dry mouth (as well as Sjogren’s, this may be a SE of drugs or radiotherapy, or simply of mouth breathing).
Two other possible causes worth asking about are food reactions (garlic and onions are obvious, but dairy products, especially yoghurt, might apparently also be an issue) and the reverse – halitosis when hungry, which is a well-recognised phenomenon whose cause was still unclear at the time of this article.
If none of the above is helpful, rare causes include:
- Metabolic disorders: uraemia, ketosis, liver failure.
- Small bowel pathology with bacterial overgrowth, such as blind loop syndrome (useful tests include FBC with haematinics – note that while Hb/ferritin/B12 may be low, red cell folate may actually be raised)
- Nasopharyngeal malignancy
- Hypochondriacal depression
