Among the more than 7000 Chinese herbal medications, only a few have been linked to episodes of clinically apparent liver injury, most commonly mentioned being Ba Jiao Lian, Chi R Yun, Jin Bu Huan, Ma Huang/Ephedra, and Shou Wu Pian. Many of these are mixtures of herbs and the composition can vary considerably despite an identical name. In other instances, the composition of the herbal mixture is totally unknown. Traditional Chinese herbal medicines are widely used in Asian communities throughout the world for a broad array of conditions. Many of these are harmless or have only minor and transient adverse effects. A few can cause hepatic injury when given in high concentrations, and some even when used in recommended doses.
When evidence of liver injury arises in a patient taking a traditional herbal medication, the appropriate response is to stop the agent and attempt to identify its nature and components. A major problem is that multiple herbs are often being taken and their exact nature and even name may not be known. The herbal products are often poorly labeled as to their composition and they may be mislabeled or contaminated with toxins, bacteria, metals or even conventional, synthetic or semisynthetic medications such as nonsteroidal antiinflammatory agents, corticosteroids, fibrates, or statins. It is helpful to collect the residual pills or extract as they may be helpful if identification is necessary. Characterization of the clinical phenotype or pattern of hepatic injury is also helpful in identifying the specific agent causing the injury. For instance, comfrey and plant pyrrolizidine alkaloids are typically associated with acute sinusoidal obstruction syndrome, whereas germander, greater celandine, usnic acid, Jin Bu Huan, Shou Wu Pian and Ma Huang (ephedra) present typically with an acute viral hepatitis-like syndrome. Pennyroyal oil and Chi R Yun (Breynia) cause acute hepatic necrosis, often accompanied by signs and symptoms of injury to other organs, such as the gastrointestinal tract, lungs, kidneys or central nervous system. Androgenic steroids cause bland cholestasis, characterized by deep jaundice and pruritus with minimal elevations in serum aminotransferase and alkaline phosphatase levels. In all situations, other causes of acute liver injury need to be excluded.