Oral adverse reactions due to cinnamon-flavoured chewing gums consumption

Cinnamon-flavoured products (toothpaste, chewing gum, food, candy and mouthwash) can cause oral adverse reactions; among these, the most common is contact stomatitis (cinnamon contact stomatitis, CCS). Signs and symptoms of contact allergic reactions affecting the oral mucosa can mimic other common oral disorders, making diagnosis difficult. As CCS may be more prevalent than believed and its clinical features can frequently determine misdiagnosis, we reviewed case reports and case series of oral adverse reactions due to cinnamon-containing chewing gums, emphasizing clinical aspects, diagnostic and management procedures. We also proposed an algorithm to perform a diagnosis of CCS as in the previous published literature the diagnostic approach was not based on a harmonized and shared evidence-based procedure. Moreover, as patients can refer to different specialists as dentists, dermatologists and allergists, a multidisciplinary approach is suggested.