Guarana was used by Natives as a daily drink, which was made by grouding seeds and mixing it with water.
Guarana claims to be useful to enhance brain function. It is used with heavy exercise routines, to stay awake, and as a stimulant for physical and intellectual stress.
IT IS ALSO RUMORED TO BE AN APHRODISIAC.
Guarana is hard to find other than in pills (energy/weighloss) or in energy drinks.