Deoxycholic acid is a a bile acid which emulsifies and solubilizes dietary fats in the intestine, and when injected subcutaneously, it disrupts cell membranes in adipocytes and destroys fat cells in that tissue. In April 2015, deoxycholic acid was approved by the FDA for the treatment submental fat to improve aesthetic appearance and reduce facial fullness or convexity. It is marketed under the brand name Kybella by Kythera Biopharma and is the first pharmacological agent available for submental fat reduction, allowing for a safer and less invasive alternative than surgical procedures. As a bile acid, deoxycholic acid emulsifies fat in the gut. Synthetically derived deoxycholic acid, when injected, stimulates a targeted breakdown of adipose cells by disrupting the cell membrane and causing adipocytolysis. This results in an inflammatory reaction and clearing of the adipose tissue remnants by macrophages. Deoxycholic acid's actions are reduced by albumin and tissue-associated proteins, therefore its effect is limited to protein-poor subcutaneous fat tissue. Protein-rich tissues like muscle and skin are unaffected by deoxycholic acid, contributing to its safety profile. Deoxycholic acid is a cytolytic agent. The physiologic effect of deoxycholic acid is by means of decreased cell membrane integrity. Deoxycholic acid inhibits miR-21 expression in primary rat hepatocytes in a dose-dependent manner, and increases miR-21 pro-apoptotic target programmed cell death 4 (PDCD4) and apoptosis. Deoxycholic acid decreases NF-κB activity, shown to represent an upstream mechanism leading to modulation of the miR-21/PDCD4 pathway.