Sodium taurodeoxycholate is a bile salt-related, anionic detergent used for isolation of membrane proteins including inner mitochondrial membrane proteins. It is formed by the conjugation of ursodeoxycholic acid (UDCA) with taurine. Sodium taurodeoxycholate and ursodeoxycholic acid are major constituents of black bear bile, which has been used in traditional Chinese medicine for thousands of years. Bear bile was historically employed to treat a number of diseases including jaundice, summer diarrhea, abdominal pain due to hepatobiliary diseases and gastric malfunction, biliary ascariasis, infectious skin diseases, the common cold, intestinal worms, and inflammation of the throat. Sodium taurodeoxycholate has been shown to inhibit apoptosis by modulating mitochondrial membrane perturbation and pore formation, B cell lymphoma 2 (Bcl-2)-associated protein X (BAX) translocation, cytochrome c release, and caspase activation. Sodium taurodeoxycholate inhibits amyloid beta (Ab)-induced apoptosis and attenuates the endoplasmic reticulum (ER) stress, which are thought to be key components of the pathological process in certain diseases. In clinical studies, Sodium taurodeoxycholate is shown to be very safe with oral administration of 1500 mg/day for up to 6 months. In a more recent clinical study, a dose of 1750 mg/day for up to 4 weeks was well tolerated in healthy obese persons. One of the major adverse effects of Sodium taurodeoxycholate is diarrhea. Based on the related information from ursodeoxycholic acid, other gastrointestinal side effects are possible including abdominal pain, flatulence, nausea, dyspepsia, and anorexia.