Found naturally in nature but big RX found it, twisted it and calls it by the name leflunomide. Leflunomide stops the progression of arthritis, RA, psoriasis, etc... by blocking an individual eczema called dihydro oritate dehydrogense. This in return blocks the progression of autoimmune diseases also the symptoms go away. Pau d'Arco is the original code for this! Naptoquininone= the active ingredient that's make the rx one work, inhibits the exact same enzyme. You get all the benefits without the chemicals. Fantastic for most autoimmune types. Here's more benefits from the amazing herb! Traditional Uses: Infections: Pau d'arco has been used to treat bacterial, fungal, and parasitic infections, including those causing fevers and malaria. Skin conditions: It's been employed to address skin ulcers, boils, and other skin issues. Gastrointestinal issues: Traditional uses include treating dysentery, stomach ulcers, and other gastrointestinal problems. Other ailments: It has also been traditionally used for conditions like arthritis, respiratory problems, and even cancer.