Mu Bing Xiao Huang is a Chinese herbal medicine based on the classical equine herbal formulas Ma Jia Wan and Wu Shi Dan. It was formulated to treat gastrointestinal stasis and impaction in a number of species, including horses, mules, cattle and goats. A single equine dose of Mu Bing Xiao Huang contains 30g Mu Xiang (Saussurea), 25-30g Bing Lang (Areca), 90- 120g Da Huang (Rheum) and 200-400g Mang Xiao (Mirabilitum). After treatment with Mu Bing Xiao Huang, 67/67 (100%) horses and mules passed feces and recovered from impaction colic. In 63/67 (94%) animals, the impaction resolved after 1 dose of Mu Bing Xiao Huang administered via a nasogastric tube. After the single dose of Mu Bing Xiao Huang, loose stool was passed within 2-4 hours in 51/63 (81%) animals and 6-8 hours in 12/63 (20%) animals. Recovery was complete in 24-48 hours. In 4 animals no effect was observed by 3 hours after administration of the 1st dose, so a 2nd dose (50% of the first dose) and intravenous fluids were administered. It took over 8 hours for feces to pass in these 4 cases, but all recovered in 72-96 hours. From the results of the retrospective study and review of similar studies in the Chinese literature, it was concluded that Mu Bing Xiao Huang can successfully treat impaction colic in horses, fore-stomach atony and impaction in cattle and goats and constipation in pigs.