2021/06/11 · Cinnamon bark is used for gastrointestinal (GI) upset, diarrhea, and gas. It is also used for stimulating appetite; for infections caused by bacteria and parasitic worms; and for menstrual cramps, the common cold, and the flu (influenza). Cinnamon bark, as part of a multi-ingredient preparation, is applied to the penis for premature ejaculation.