Nature's Harmony Cascara Sagrada is a gentle herbal laxative. It is believed to have a tonic effect on the muscles of the colon wall, helping to restore the bowel to its normal function. Each capsule of Nature's Harmony Cascara Sagrada contains 450 mg of cascara sagrada (Rhamnus purshiana) bark, providing 7% hydroxyanthracene (HAD) derivative. This product is free of corn, dairy, egg, gluten, lactose, nuts, shellfish, sodium, soy, starch, sugar, sulphites, yeast, and artificial colours, flavours, and preservatives.