The active ingredients in every Listerine bottle are essential oils such as thymol, menthol, eucalyptol and methyl salicylate. The inactive ingredients include caramel, water and alcohol in addition to sodium benzoate, poloxamer 407 and benzoic acid.
The combination of Listerine's active ingredients has anti-inflammatory and antiseptic effects. Ethanol can eliminate bacteria when included in concentrations of 40 percent or higher. In Listerine, however, it is present in concentrations of 26.9 or 21.6 percent and instead serves to dissolve the active ingredients. Menthol is present in a concentration of 0.042 percent, while eucalyptol has a concentration of 0.092 percent, and thymol has 0.064 percent.
Listerine is an antiseptic mouthwash that has been clinically proven to be very effective at killing germs that might cause bad breath. It was invented in the 19th century as a surgical antiseptic. Johnson & Johnson has been manufacturing and distributing the product since 2006. All the ingredients in Listerine are recommended by the American Dental Association. The manufacturer claims that the product offers 24-hour protection against germs. Popular flavors of this mouthwash include Cool Mint, Soft Mint, Fresh Citrus, Arctic Mint and Vanilla Mint. Other available flavors include Fresh Mint, Herbal Mint, Natural Citrus and Original Listerine.