NOW Liver Refresh is a proprietary blend of herbs and nutrients designed to support healthy liver function. This product features milk thistle extract which has been shown in clinical and non-clinical studies to support the liver as measured by standard liver enzyme laboratory tests. In addition this formula also features N-acetyl cysteine and methionine two amino acids known to enhance the production of glutathione in the liver. Glutathione a major cellular antioxidant plays an essential role in liver detoxification mechanisms. Also included are other herbs (schisandra barberry and scute) that have been shown in non-clinical studies to support healthy liver function.