Kola Nut, Cola Nut

"The kola nut is the fruit of the kola tree, a genus (Cola) of trees that are native to the tropical rainforests of Africa. The caffeine-containing fruit of the tree is used as a flavoring ingredient in beverages, and is the origin of the term "cola"." [source: Wikipedia]

According to the United States FDA [link] the kola nut is generally recognized as safe.

Kola nut - ESO ("Essential oil and/or oleoresin"), GRAS ("generally recognized as safe" [link]), GMP ("In accordance with good manufacturing practices; or sufficient for purpose; or quantity not greater than required")