Toothpaste can contain ingredients that cause cheilitis in allergic individuals, according to the U.S. National Library of Medicine. Researchers found that the flavoring in toothpaste was the most common cause for allergic cheilitis.
In addition to flavoring, cocamidopropyl betaine, essential oils, parabens, propoylene glycol and propolis are common toothpaste ingredients that potentially cause allergic contact cheilitis, explains the U.S. National Library of Medicine. Determining the actual cause of allergy is often difficult. Most commercial toothpaste brands use mint or cinnamon flavoring. Health care professionals may opt to recommend low-flavor or flavorless toothpaste brands to patients who experience allergic reactions to typical toothpaste brands.