Mouthwash and oral cancer: carcinogen or coincidence?

Among 200 patients with squamous cell cancer of the head and neck, 11 persons abstained from all alcoholic beverages and tobacco. All but one of these 11 patients had used mouthwash many times daily for more than 20 years. Most of them used a brand of mouthwash that contained 25% alcohol. This evidence, along with information from other patients, may be used to confirm or refute the theory that mouthwash may be carcinogenic for susceptible persons.