Purified dry extract of Paullinia cupana (guaraná) (PC-18) for chemotherapy-related fatigue in patients with solid tumors: an early discontinuation study.

Purpose: Paullinia cupana (guaraná) is an Amazonian plant that has been previously shown to be effective in treating chemotherapy-related fatigue (CRF) in patients with breast cancer. We aimed to evaluate the efficacy of a purified dry extract of P. cupana (PC-18) in patients with various solid tumors treated with chemotherapy.