WARNING: The alcohol in mouthwash, and the alcohol contained in liquor, isn't the same thing. The alcohol in liquor, wine or beer is grain (ethyl) alcohol. The stuff in mouthwash, on the other hand, is denatured. Don't be surprised if you develop gastroenteritis. Also, Listerine contains phenol compounds, which may contribute to a severe anion-gap metabolic acidosis and osmolar gap, multiorgan system failure, and death.
24 year professional paramedic firefighter.