The major use of sodium oxybate is in treating two of the symptoms of narcolepsy – cataplexy (sudden muscle weakness) and excessive daytime sleepiness. Reviews of sodium oxybate concluded that it is well tolerated and associated with "significant reductions in cataplexy and daytime sleepiness," and that its effectiveness "in treating major, clinically relevant narcolepsy symptoms and sleep architecture abnormalities" has been established. However, because of the risks of abuse associated with this medication, it is available in the US only through a risk evaluation and mitigation strategy (REMS) program mandated by the FDA. The program requires that providers who prescribe it are certified to do so, that it is dispensed only from a central pharmacy that is certified to do so, and people to whom it is prescribed must be enrolled in a program for the drug and must document that they are using the drug safely.