Clenbuterol-HCl was a synthetic drug, which was used to treated asthma or beast bronchus as bronchia expending drug in human clinic medicine firstly.

• “瘦肉精”（盐酸克伦特罗）最初作为支气管扩张剂应用于人类临床医学，当人们发现其具有促进畜禽脂肪分解，提高胴体瘦肉率的作用后又被作为添加剂广泛应用于动物饲料生产中。