Testosterone Undecanoate is a fatty acid ester of the natural hormone testosterone. Following oral administration it is co-absorbed with the castor oil from the intestine into lymphatic system, thus bypassing the hepatic system to avoid inactivation of testosterone by the liver. From the lymphatic system it is released into the blood in vein. Single administration of Testanon 250 increases total plasma testosterone. Inside the cell this hormone goes through the process of protein synthesis and thus translating required structural protein and enzyme.