This article describes the status of Xyrem as a prescription drug. To learn about the chemical and its biological mode of action, see the article on gamma-hydroxybutyric acid. Xyrem's a trade name for gamma-hydroxybutyric acid or GHB, an endogenous neurochemical involved in regulating metabolism, especially regarding sleep or hibernation. In medical contexts GHB's often called sodium oxybate, which's an alternate term for the sodium salt of the chemical. Approval Process and Legal Status GHB has… (More on Xyrem)