The US Food and Drug Administration has moved to prevent a seller of dietary herbal products from marketing its products as recreational drugs.

The FDA says it e-mailed Xoch Linnebank, a Dutch online seller of Yellow Jackets, warning it that promoting the pills as a "herbal ecstasy" is illegal. Yellow Jackets contain ephedra, a legal dietary supplement, and other stimulants such as caffeinating kola nut.

Earlier this year, the FDA sent a warning letter to a Tennessee company Herbtech marketing two ephedra products as street drug alternatives. The FDA will soon be conducting a scientific review of ephedra and recommending strong warning labels for products containing the herbal compound.