Pau Pereira (Geissospermum vellosii) is an Amazon rainforest tree and it is traditionally used as a febrifuge (lowers fever) by the indians, and its bark extract is used to treat malaria, digestive disorders and cancers. Pau Pereira extract is rich in β-carboline alkaloids and exhibited anti-proliferative activities against melanoma and glioblastoma, ovarian cancer and pancreatic cancer.