This section is from the book "A Practitioner's Handbook Of Materia Medica And Therapeutics", by Thos. S. Blair. Also available from Amazon: A Practitioner's handbook of Materia Medica and Therapeutics.
Guarana. This is the Brazilian cocoa. The natives, who roast and grind the seeds and make a beverage of them, much value this sort of chocolate as a tonic and mild nerve stimulant. It contains considerable caffeine and volatile oil, and possesses a tonic and restorative effect in the gastro-intestinal disorders, inclining toward chronic diarrhea. The fluidextract is successfully used in sick headache in doses of 10 to 30 I.. In a great many cases in which the official fluidextractum cocae is used, guarana would give just as good results without the danger of implanting a drug habit. The average dose of the U. S. P. f.e. coca contains 1-7 gr. of coca alkaloids.