Evening primrose is a plant with yellow flowers native to North America. Its seeds are used to produce evening primrose oil, also sometimes called night willow herb, fever plant, or King’s cure-all.Native Americans used evening primrose oil to heal wounds and treat issues like stomach pain and sore throat. By the 17th century, it became a popular folk remedy in Europe where it earned the nickname “King’s cure-all”. Our Evening Primrose capsules are nothing short of amazing. Each capsule contains 1300mg of goodness. providing 117mg of Gamma Linolenic Acid (GLA) and 15mg of Vitamin E.