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British Dental Journal 207, E19 (2009) Published online: 28 November 2009 | doi:10.1038/sj.bdj.2009.1014


Subject Categories: Oral cancer | Preventive dentistry

Are alcohol containing mouthwashes safe?
C .W. de A. Werner1 & R. A. Seymour2

Dentists need to be aware that there is a hypothetical risk of the development of oral cancer from repeated use of alcohol containing mouthwashes...

Alcohol (ethanol) is a constituent of many proprietary mouthwashes. Some studies have shown that regular use of such mouthwashes can increase the risk of developing oral cancer. Recently, the evidence has been reviewed by two separate authors. The conclusions from these reviews are conflicting... The evidence suggests that the alcohol component of mouthwashes affords little additional benefit to the other active ingredients in terms of plaque and gingivitis control. In view of this outcome and the hypothetical risk of oral cancer, it would seem prudent that members of the dental team advise their patients accordingly.

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The summary of the research above done in 2009 suggests that evidence does not support mouthwash as cause of oral cancer because some studies suggest it does whilst others suggest it doesn't. Until there is a large,strong study that is able to conclusively show one way or the other, we cannot say that mouthwash causes cancer. However, avoidance of alcohol containing mouthwashes might be prudent, NOT because it has been proven to cause cancer but because it adds nothing in terms of benefit to oral hygiene and may still have a part to play when considering the logic.