This section is from the book "Materia Medica And Therapeutics: An Introduction to the National Treatment of Disease", by John Mitchell Bruce. Also available from Amazon: The pharmacology and therapeutics of the materia medica.
Characters. - Cylindrical rolls of dried paste. Brazilian cocoa.
Composition. - Guarana contains no less than five per cent. of caffein, C8H10N4O2, the alkaloid of the coffee and tea plants; united, as in these, with tannic acid, starch, and gum.
Dose. - 15 to 60 gr. in powder, or as infusion.
The action of guarana closely resembles that of strong tea or coffee. It is chiefly used in sick headache (megrim). See Caffein (page 271).