Chaparral has been used traditionally as a remedy for bronchitis, colds, rheumatism, stomach pain, venereal disease, and chicken pox. It promotes sweating and improves the elimination of toxins from the liver and skin. Chaparral's antibacterial activity makes it useful externally for skin abrasions or injuries. It is used as a douche for trichomonas. Chaparral contains NDGA, a substance used by the food industry to prevent fermentation and decomposition; this constituent may account for its antioxidant activity. It is a famous cancer remedy, and American herbalists think of it as a concentrated extract applied externally for skin cancer and sometimes recommend the powdered herb in capsules or tablets, or the tea as a cancer-preventative or remedy. Scientific provings for antitumor activity with this herb are inconclusive.