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Discover a lower-sodium oxybate treatment option

XYWAV has the same amount of oxybate as sodium oxybate, with 92% less sodium in each nightly dose

If you are currently taking XYREM, transitioning to XYWAV can help treat your narcolepsy symptoms of cataplexy or EDS while helping you to reduce the amount of sodium you take in with your medication.

Although the new XYWAV bottle is smaller than the XYREM bottle, both bottles contain the same amount of medicine: 180 mL.

The efficacy and safety of XYWAV were demonstrated

The exact way XYWAV works for the treatment of narcolepsy is unknown. XYWAV is thought to work while you sleep to help with symptoms of cataplexy and EDS during the day.

The efficacy of XYWAV for treatment of cataplexy and EDS in adult patients with narcolepsy was demonstrated in a clinical trial.

The effectiveness of XYWAV in pediatric patients is based upon a clinical study in patients treated with XYREM.

Understanding common side effects in patients treated with XYWAV

The most common side effects in adult patients treated with XYWAV in the clinical trial were headache, nausea, dizziness, decreased appetite, parasomnia, diarrhea, excessive sweating, anxiety, and vomiting.

  • In patients who remained on treatment, side effects tended to occur early and diminish over time
  • Adverse reactions related to XYWAV were reported less frequently, as an overall incidence, in patients taking XYREM at study entry than in XYREM-naïve patients

In children, the most common side effects include bedwetting, nausea, headache, vomiting, weight decrease, decreased appetite, and dizziness.

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XYWAV™ (calcium, magnesium, potassium, and sodium oxybates) oral solution, 0.5 g/mL total salts (equivalent to 0.413 g/mL of oxybate) is a prescription medicine used to treat the following symptoms in people 7 years of age or older with narcolepsy:

  • sudden onset of weak or paralyzed muscles (cataplexy)
  • excessive daytime sleepiness (EDS)

Important Safety Information

WARNING: Taking XYWAV with other central nervous system (CNS) depressants such as medicines used to make you or your child fall asleep, including opioid analgesics, benzodiazepines, sedating antidepressants, antipsychotics, sedating anti-epileptic medicines, general anesthetics, muscle relaxants, alcohol, or street drugs, may cause serious medical problems, including trouble breathing (respiratory depression), low blood pressure (hypotension), changes in alertness (drowsiness), fainting (syncope), and death.

The active ingredient of XYWAV is a form of gamma hydroxybutyrate (GHB). Abuse or misuse of illegal GHB alone or with other drugs that cause changes in alertness (or consciousness) has caused serious side effects. These effects include seizures, trouble breathing (respiratory depression), changes in alertness (drowsiness), coma, and death. Call your doctor right away if you or your child has any of these serious side effects.

Because of these risks, you have to go through the XYWAV and XYREM REMS Program to have your or your child’s prescription for XYWAV filled.

Do not take XYWAV if you take or your child takes other sleep medicines or sedatives (medicines that cause sleepiness), drinks alcohol, or has a rare problem called succinic semialdehyde dehydrogenase deficiency.


Keep XYWAV in a safe place to prevent abuse and misuse. Selling or giving away XYWAV may harm others, and is against the law. Tell your doctor if you have ever abused or been dependent on alcohol, prescription medicines, or street drugs.


Anyone who takes XYWAV should not do anything that requires them to be fully awake or is dangerous, including driving a car, using heavy machinery, or flying an airplane, for at least 6 hours after taking XYWAV. Those activities should not be done until you know how XYWAV affects you or your child.


XYWAV can cause serious side effects, including the following:

  • Breathing problems, including slower breathing, trouble breathing, and/or short periods of not breathing while sleeping (sleep apnea). People who already have breathing or lung problems have a higher chance of having breathing problems when they use XYWAV.
  • Mental health problems, including confusion, seeing or hearing things that are not real (hallucinations), unusual or disturbing thoughts (abnormal thinking), feeling anxious or upset, depression, thoughts of killing yourself or trying to kill yourself, increased tiredness, feelings of guilt or worthlessness, or difficulty concentrating. Tell your doctor if you or your child have or had depression or have tried to harm yourself or themselves. Call your doctor right away if you have or your child has symptoms of mental health problems or a change in weight or appetite.
  • Sleepwalking. Sleepwalking can cause injuries. Call your doctor if you or your child starts sleepwalking. Your doctor should check you or your child.


The most common side effects of XYWAV in adults include headache, nausea, dizziness, decreased appetite, parasomnia (a sleep disorder that can include abnormal dreams, abnormal rapid eye movement (REM) sleep, sleep paralysis, sleep talking, sleep terror, sleep-related eating disorder, sleep walking, and other abnormal sleep-related events), diarrhea, excessive sweating (hyperhidrosis), anxiety and vomiting.


The most common side effects of XYWAV in children include bedwetting, nausea, headache, vomiting, weight decrease, decreased appetite, and dizziness.


XYWAV can cause physical dependence and craving for the medicine when it is not taken as directed. These are not all the possible side effects of XYWAV.


You are encouraged to report negative side effects of prescription drugs to the FDA. Visit, or call 1-800-FDA-1088.


Please see full Prescribing Information, including BOXED Warning, and Medication Guide.