Rev Paul Med. 1994 Jul-Sep; 112(3): 607-11.

Acute effects of the Paulinia cupana, "GuaranÃ¡" on the cognition of normal volunteers.

GaldurÃ³z JC, Carlini Ede A.

Clinical Psychobiology Research Center of the CEBRID Brazilian Center for Information on Psychotropic Drugs of the Escola Paulista de Medicina, SÃ£o Paulo.

The authors studied the acute effects of "GuaranÃ¡", when compared to caffeine and placebo, (double blind study) on cognition, anxiety and sleep in 30 normal volunteers. Although results were negative it cannot be concluded that "GuaranÃ¡" is harmless. Other studies shall be undertaken, administering "GuaranÃ¡" on a long term basis, as popularly proclaimed.