Swanson Full Spectrum Sarsaparilla Root Native to Central and South America, this plant was introduced to Europe in the 16th century for use as a tonic. Widely accepted as a blood purifier, sarsaparilla is also considered a tonic for overall health and well-being. Native Americans used sarsaparilla for stomach and skin health and to promote respiratory, kidney and urinary tract health. Each two-capsule serving of Swanson Full Spectrum Sarsaparilla Root provides 900mg of sarsaparilla root. Full Spectrum Sarsaparilla Root: Traditionally used for kidney, urinary tract and skin health, General tonic for overall health, Full Spectrum Sarsaparilla Root Formula. Dosage: Take 2 capsules daily with water.