Cholestasis can be caused by a variety of reasons, not just by liver or bile duct causes alone. Cholestasis can be categorized into intrahepatic cholestasis and extrahepatic cholestasis, and the causes of the two types of cholestasis are different. 1. Causes of intrahepatic cholestasis: Intrahepatic cholestasis refers to the accumulation of bile due to impaired metabolism or excretion of bile in the liver, and in severe cases, bile can even flow back into the bloodstream. The common causes of intrahepatic cholestasis are viral hepatitis, autoimmune liver disease, alcoholic liver disease, drug liver injury and so on. 2. Causes of extrahepatic cholestasis: Extrahepatic cholestasis is often caused by tumors, stones, parasites, inflammation, infection, stenosis and other conditions in the extrahepatic bile ducts, resulting in bile not being able to flow through the extrahepatic bile ducts, etc. When treating this condition, surgical treatments are usually needed to relieve the obstruction of the extrahepatic bile ducts. For patients with or suspecting cholestasis, they should immediately go to the relevant departments of regular hospitals and be treated under the guidance of specialized physicians to avoid delays.