China\'s drug watchdog has reiterated that online drug vendors may not sell compound preparations or prescription drugs containing ephedrine, in the latest effort to regulate drug sales online. According to a circular released on Tuesday by the China Food and Drug Administration, qualifications in Internet drug trading services are required for pharmaceutical producers or trading enterprises to conduct online drug business, and high-street drug retailers must check and register the identities of those who buy compound preparations or prescription drugs with ephedrine. The circular was issued after the watchdog found more more than 2,000 Chinese websites to be allegedly involved in selling drugs illegally two weeks ago. In addition, high-street drug retailers are also prohibited from showcasing or promoting ephedrine-based drugs to consumers on drug trading websites, the circular added. Under China\'s food and drug regulation, online drug vendors must be approved by authorities. They may only sell over-the-counter drugs at present, and online sales of prescription drugs and those containing ephedrine are prohibited. Ephedrine is the primary ingredient in methamphetamine.