The review found one small, low quality randomized controlled trial which did not demonstrate a therapeutic effect of capsaicin on allergic rhinitis symptoms.

Also disclosed is a method for skin lightening in mammals comprising topically applying to the skin said skin lightening cosmetic composition.

Animal experiments showed that local application of the skin and mucous membrane of about 1g total N-nitrosamines, it will induce local or systemic tumors, especially liver cancer.