Chi R Yun is the Chinese proprietary name for extracts of Breynia officinalis, which has been used as an herbal medication alone and in combination with other botanicals to treat a variety of conditions including heart failure, venereal disease, growth retardation, contusions and conjunctivitis. Taken in higher than recommended doses, breynia is considered a poison and can cause gastrointestinal, hepatic, urinary and respiratory injury.