Guarana (Paullinia cupana)

Guarana (Paullinia cupana) is a plant native to the central Amazon and has been used medicinally for centuries. It has a popular reputation of being a stimulant and an aphrodisiac, as well as exhibiting gastric-protective effects. Guarana contains caffeine and other similar chemicals and has been used for the treatment of diarrhea, weight loss, and fatigue. Evaluation in patients with cancer has been performed related to the symptoms of fatigue, hot flashes, sleep-wake disturbances, and depression.