Guarana (22% Caffeine)

History and Uses:
Guarana is a climbing shrub native to South America. The indigenous people of the Amazon rain forest used crushed Guarana seed both as a beverage and a medicine. Besides its refreshing and nutritive value, Guarana was said to treat diarrhea, decrease fatigue, reduce hunger and help relieve arthritis. It also has a history of use in treating hangovers from alcohol abuse and headaches related to menstruation. The plant was introduced into France by a physician returning from Brazil, and it came to be employed in the treatment of migraine and nervous headaches, neuralgia, paralysis, urinary tract irritation and other ailments, as well as continuing to be administered for chronic diarrhea. A beverage is made from Guarana sticks by grating half a tablespoonful into sugar and water and drinking it like tea. Brazilian miners drink Guarana constantly and believe it to be a preventive of many diseases, as well as a most refreshing beverage. It is said to be of benefit for nervous headache or the distress that accompanies menstruation or even exhaustion following dissipation. It is not recommended for chronic headache or in cases where it is not desirable to increase body temperature or excite the heart or increase arterial tension. Primary chemical constituents of this herb include caffeine, theophylline, theobromine, guaranine, tannins and saponins. Guaranine (which is nearly identical to caffeine) and the closely related alkaloids, theobromine and theophylline, make up the primary active agents in Guarana. Caffeine's effects (and hence those of guaranine) are well known, and include stimulating the central nervous system, increasing metabolic rate and having a mild diuretic effect. Caffeine may have adverse effects on the blood vessels and other body systems as well as on a developing fetus; and presumably, guaranine would have similar effects, but this has not yet been proven. Though Guarana contains caffeine, it is more slowly absorbed into the gastrointestinal tract and thus is said to have a longer-lasting effect than coffee. The tannins, which are astringent, help to curb diarrhea. Guarana has also shown some ability to inhibit blood platelet aggregation, and the herb is considered a nervous system stimulant.