Skip to Content

Xywav

Generic name: calcium, magnesium, potassium, and sodium oxybates

What is Xywav?

Xywav 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), or
  • excessive daytime sleepiness (EDS)

It is not known if Xywav is safe and effective in children less than 7 years of age.

What is the most important information I should know about Xywav?

  • Xywav is a central nervous system (CNS) depressant. Taking Xywav with other 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
    • death
      Ask your doctor if you are not sure if you are, or your child is, taking a medicine listed above.
  • Xywav is a federal controlled substance (CIII). The active ingredient of Xywav is a form of gammahydroxybutyrate (GHB) that is also a federal controlled substance (CI). Abuse of illegal GHB, either alone or with other CNS depressants, may cause serious medical problems, including:
    • seizure
    • trouble breathing (respiratory depression
    • changes in alertness (drowsiness
    • coma
    • death
      Call your doctor right away if you have or your child has any of these serious side effects.
  • 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.
  • 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.
  • Because of the risk of CNS depression, abuse, and misuse, Xywav is available only by prescription, and filled through the central pharmacy in the Xywav and Xyrem REMS Program. You or your child must be enrolled in the Xywav and Xyrem REMS to receive Xywav. Before you receive or your child receives Xywav, your doctor or pharmacist will make sure that you understand how to take Xywav safely and effectively. If you have any questions about Xywav, ask your doctor or call the Xywav and Xyrem REMS at 1-866-997-3688.

Who should not take Xywav?

Do not take Xywav if you or your child:

  • takes other sleep medicines or sedatives (medicines that cause sleepiness)
  • drinks alcohol
  • has a rare problem called succinic semialdehyde dehydrogenase deficiency

What should I tell my healthcare provider before taking Xywav?

Before taking Xywav, tell your doctor about all medical conditions, including if you or your child:

  • have a history of drug abuse.
  • have short periods of not breathing while sleeping (sleep apnea).
  • has trouble breathing or has lung problems. You or your child may have a higher chance of having serious breathing problems when taking Xywav.
  • have or had depression or has tried to harm yourself or themselves. You or your child should be watched carefully for new symptoms of depression.
  • has or had behavior or other psychiatric problems such as:
    • anxiety
    • seeing or hearing things that are not real (hallucinations)
    • feeling more suspicious (paranoia)
    • being out of touch with reality (psychosis)
    • acting aggressive
    • agitation
  • have liver problems.
  • are pregnant or plan to become pregnant. It is not known if Xywav can harm your unborn baby.
  • are breastfeeding or plan to breastfeed. Xywav passes into breast milk. You and your doctor should decide if you or your child will take Xywav or breastfeed.

Tell your doctor about all the medicines you take or your child takes, including prescription and over-the-counter medicines, vitamins, and herbal supplements.
Especially, tell your doctor if you take or your child takes other medicines to help you or your child sleep (sedatives). Know the medicines you take or your child takes. Keep a list of them to show your doctor and pharmacist when you get or your child gets a new medicine.

How should I take Xywav?

  • Read the Instructions for Use that comes with Xywav.
  • Take or give Xywav exactly as your doctor tells you to take or give it. Your doctor may change the dose or dosing routine if needed.
  • Wait at least 2 hours after eating before taking or giving Xywav.
  • Xywav can cause physical dependence and craving for the medicine when it is not taken as directed.
  • Never change the dose without talking to your doctor.
  • Xywav can cause sleep very quickly without feeling drowsy. Some people fall asleep within 5 minutes and most fall asleep within 15 minutes. The time it takes to fall asleep might be different from night to night.
  • Falling asleep quickly, including while standing or while getting up from the bed, has led to falls with injuries that have required some people to be hospitalized.
  • Xywav is taken at night divided into 2 doses.
    • Adults: Take the first Xywav dose at bedtime while you are in bed and lie down immediately. Take the second Xywav dose 2½ to 4 hours after the first Xywav dose. You may want to set an alarm clock to make sure you wake up to take the second Xywav dose. You should remain in bed after taking the first and second doses of Xywav.
    • Children: Give the first Xywav dose at bedtime or after an initial period of sleep, while your child is in bed and have them lie down immediately. Give the second Xywav dose 2½ to 4 hours after the first Xywav dose. You may want to set an alarm clock to make sure you wake up to give the second Xywav dose. Your child should remain in bed after taking the first and second doses of Xywav.
  • If you miss or your child misses the second Xywav dose, skip that dose and do not take or give Xywav again until the next night. Never take or give 2 Xywav doses at 1 time.
  • If you take or your child takes too much Xywav, call your doctor or go to the nearest hospital emergency room right away.

What are the possible side effects of Xywav?

Xywav can cause serious side effects, including:

  • See “What is the most important information I should know about Xywav?
  • breathing problems, including:
    • slower breathing.
    • trouble breathing.
    • 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 take 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
    • difficulty concentrating
      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 start or your child starts sleepwalking. Your doctor should check you or your child.

The most common side effects of Xywav in adults include:

  • headache
  • diarrhea
  • nausea
  • excessive sweating (hyperhidrosis)
  • dizziness
  • anxiety
  • decreased appetite
  • vomiting
  • 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)

The most common side effects of Xywav in children include:

  • bedwetting
  • weight decrease
  • nausea
  • decreased appetite
  • headache
  • dizziness
  • vomiting

These are not all the possible side effects of Xywav. For more information, ask your doctor or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

General information about the safe and effective use of Xywav

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use Xywav for a condition for which it was not prescribed. Do not give Xywav to other people, even if they have the same symptoms. It may harm them.
You can ask your pharmacist or doctor for information about Xywav that is written for health professionals.

How should I store Xywav?

  • Store Xywav in the original bottle prior to mixing with water. After mixing with water, store Xywav in the pharmacy containers with child-resistant caps provided by the pharmacy.
  • Store Xywav at room temperature between 68°F to 77°F (20°C to 25°C).
  • Xywav solution prepared after mixing with water should be taken within 24 hours.
  • When you have finished using a Xywav bottle:
    • empty any unused Xywav down the sink drain.
    • cross out the label on the Xywav bottle with a marker.
    • place the empty Xywav bottle in the trash. Xywav comes in a child-resistant package.

Keep Xywav and all medicines out of the reach of children and pets.

What are the ingredients in Xywav?

Active ingredients: calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate (gammahydroxybutyrate (GHB))

Inactive ingredients: purified water and sucralose

For more information, go to www.XYWAVXYREMREMS.com or call the XYWAV and XYREM REMS at 1-866-997­ 3688.

Source: Food and Drug Administration (FDA). Last updated July 21, 2020.