Because there is no evidence of effectiveness, sassafras should not be used to treat rheumatoid arthritis, infections, or any other medical condition.
Sassafras is a pernnial tree native to Eastern United States. The Native Americans used infusions made from the root bark as a remedy to treat fevers, diarrhea and rheumatism. Sassafras contains safrole, a volatile oil, which showed anticancer effects in lab and animal studies, but it is also a carcinogen. Human studies have not yet been conducted.
Sassafras is a pernnial tree native to Eastern United States. The Native Americans used infusions made from the root bark as a remedy to treat fevers, diarrhea and rheumatism. Sassafras oil, extracted from the root bark, is used to perfume soaps and to flavor tea and rootbeer.
Oral administration of safrole significantly improved the diabetic condition in Streptozotocin-induced diabetic rats (12), but human studies are lacking.
Pharmacological studies revealed that sassafras oil contains safrole, a volatile oil, that exerts anticancer effects in vitro and in animal models (7)(8)(9)(10)(11). However, safrole has also been shown to be a potent carcinogen (5)(13). Based on these data, the FDA classified safrole as a Substance Generally Prohibited From Direct Addition or Use as Human Food (14).
Safrole, the main active constituent, shows cytotoxic effects in human tongue squamous carcinoma SCC-4 cells by apoptosis via the mitochondria- and caspase-dependent signal pathways (7); and through the endoplasmic reticulum stress and intrinsic signaling pathways in human leukemia HL-60 cells(9). It also suppressed myelomonocytic leukemia WEHI-3 cells in vivo, and stimulated macrophage phagocytosis and natural killer cell cytotoxicity in leukemic mice (8).
Toxic effects of safrole in Madin-Darby canine kidney (MDCK) cells were shown to be via induction of an increase in cytosolic free Ca2+ by causing Ca2+ release from the endoplasmic reticulum in a phospholipase C- and protein kinase C-independent fashion, and by inducing Ca2+ influx(16).