Guarana is used in soft drinks and energy shots, or as an ingredient in herbal tea, or contained in capsules. It is rich in caffeine, and is of interest for its potential effects on cognition and energy. It actually contains about twice the caffeine found in coffee beans, and most of the caffeine obtained by South America is from guarana. Following the discovery of guarana by Father Felip Betendorf, the plant was introduced to western civilization in the 17th century. By 1958, guarana was commercialized. Botanist James Duke cites past and present tribal uses in the rainforest: as a preventive for arteriosclerosis; as an effective cardiovascular drug; as an pain-reliever, astringent, stimulant, and tonic used to treat diarrhea, hypertension, fever, migraine, neuralgia, and dysentery.