• A patient had acute stomatitis and dermatitis due to a popular toothpaste containing cinnamon oil flavor. Cinnamon cassia oil is known as a topical sensitizer and was demonstrated to be the offending allergen. Cinnamic aldehyde and related chemicals are used widely, so that patients having cinnamon allergy may be exposed to many sources. There is difficulty in diagnosing allergic contact stomatitis.
(Arch Dermatol 112:202-203, 1976)
Drake TE, Maibach HI. Allergic Contact Dermatitis Cinnamic Aldehyde-Flavored and Stomatitis Caused by a Toothpaste. Arch Dermatol. 1976;112(2):202-203. doi:10.1001/archderm.1976.01630260026007