Inhibition of orally produced volatile sulfur compounds by zinc, chlorhexidine or cetylpyridinium chloride--effect of concentration

Eur J Oral Sci. 2003 Oct;111(5):400-4. doi: 10.1034/j.1600-0722.2003.00063.x.


Zinc ions, chlorhexidine (CHX) and cetylpyridinium chloride (CPC) are all known to inhibit production of volatile sulfur compounds (VSCs). The objective was to examine the anti-VSC dose-response effects of each of the above agents. Oral malodor was induced in 13 test subjects using the cysteine challenge method. The oral VSC response to rinses with 6 mm l-cysteine (pH 7.2) before and 1, 2 and 3 h after rinsing with zinc ions (Zn2+: 0.1, 0.3 and 1.0%), CHX and CPC (0.025 and 0.2%) was measured. Mouth air was analysed for VSC by gas chromatography (GC) according to current methodology. Zinc had a marked dose- and time-dependent anti-VSC effect. Zinc at 1% concentration had a somewhat unpleasant taste, whereas the lowest concentration was found acceptable. Chlorhexidine maintained a moderate anti-VSC effect over time. At 3 h, 0.2% CHX was the most effective agent but tasted relatively unpleasant. Cetylpyridinium at a concentration of 0.2% was only marginally more effective than 0.025% CHX over the 3 h, while 0.025% CPC had no better anti-VSC effect than water at both 2 h and 3 h. It was concluded that the three test agents demonstrated different anti-VSC kinetics. Although Zn had the best anti-VSC effect at 1 h, 0.2% CHX was at least as effective as 1% Zn at 3 h, most likely as a result of its unique substantivity.

MeSH terms

  • Adult
  • Aged
  • Analysis of Variance
  • Anti-Infective Agents, Local / administration & dosage*
  • Cetylpyridinium / administration & dosage*
  • Chlorhexidine / administration & dosage*
  • Chromatography, Gas
  • Cysteine / antagonists & inhibitors
  • Dose-Response Relationship, Drug
  • Female
  • Halitosis / therapy*
  • Humans
  • Male
  • Middle Aged
  • Mouthwashes / therapeutic use
  • Sulfur Compounds / analysis
  • Sulfur Compounds / antagonists & inhibitors*
  • Taste / drug effects
  • Zinc / administration & dosage*


  • Anti-Infective Agents, Local
  • Mouthwashes
  • Sulfur Compounds
  • Cetylpyridinium
  • Zinc
  • Cysteine
  • Chlorhexidine