Background: In patients with breast cancer (BC) undergoing systemic chemotherapy, cancer-related fatigue (CRF) is a common problem that can negatively impact quality of life. Guarana (Paullinia cupana) is a plant native to the Amazon basin that has been used as a stimulant since pre-Columbian times.
Objective: The purpose of this study was to evaluate the effectiveness of guarana extract on fatigue, sleep quality, anxiety, depression symptoms, and menopause in a group of BC chemotherapy patients.
Patients and methods: Patients with progressive fatigue after their first cycle of chemotherapy were randomized to receive either guarana 50 mg by mouth twice daily (32 patients) or placebo (43 patients) for 21 days. After a 7-day washout period, patients were crossed over to the opposite experimental arm. All patients were evaluated on days 1, 21, and 49. The primary endpoint was the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) questionnaire score, and secondary endpoints were the results of the Functional Assessment of Chronic Illness Therapy-Endocrine Symptoms (FACT-ES), Brief Fatigue Inventory (BFI), Pittsburg Sleep Quality Index, Chalder Fatigue Scale, and Hospital Anxiety and Depression Scale.
Results: Guarana significantly improved the FACIT-F, FACT-ES, and BFI global scores compared to placebo on days 21 and 49 (p < 0.01). The Chalder Scale improved significantly on day 21 (p < 0.01) but not on day 49 (p = 0.27). Guarana did not produce any Common Terminology Criteria for Adverse Events grades 2, 3, or 4 toxicities and did not worsen sleep quality or cause anxiety or depression.
Conclusions: Guarana is an effective, inexpensive, and nontoxic alternative for the short-term treatment of fatigue in BC patients receiving systemic chemotherapy. Further studies are needed to confirm these results and to evaluate their generalizability to chronic CRF and to other types of cancer.