Xywav is a medication that contains calcium, magnesium, potassium, and sodium oxybates. It's a central nervous system (CNS) depressant that's used to treat cataplexy (sudden muscle weakness) or excessive daytime sleepiness in people ages 7 years and older with narcolepsy. This medication can also treat idiopathic hypersomnia (IH) in adults. Xywav is a liquid that's taken by mouth twice each night, but some people with IH can take it just once at night. Some side effects can include headache, nausea, and dizziness.
Cataplexy (sudden muscle weakness) or excessive daytime sleepiness (EDS) in people ages 7 years and older with narcolepsy
Idiopathic hypersomnia (IH) in adults
Xywav belongs to the drug class known as CNS depressants. It's not exactly known how Xywav works for narcolepsy and IH, but it's thought to work by raising the activity of gamma-aminobutyric acid (GABA) in the areas of the brain that control sleep and wakefulness.
Xywav can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking medications that can slow the body down and cause slow breathing | Drinking alcohol | Medical conditions that cause breathing problems (e.g., COPD, asthma, sleep apnea)
Xywav is a central nervous system (CNS) depressant that slows down the activity of your brain and your nerves. This can cause you to be less alert or have dangerously slowed breathing, even at recommended doses of Xywav.
Don't take Xywav with other CNS depressants. Otherwise, it might put you at risk for breathing problems, low blood pressure, extreme sleepiness, and even death. These medications include opioid pain medications; benzodiazepines; muscle relaxants; and any other medications that cause drowsiness. People with medical conditions like obstructive sleep apnea can have a higher risk of experiencing breathing problems while they're taking Xywav.
Let your prescriber and care team know about your full medical history and provide them with an up-to-date list of all the medications you take. They can make sure Xywav is safe for you to take and also check whether any of your medications need to be adjusted. Don't drive or operate any machinery until you know that Xywav doesn't affect your concentration, judgment, or motor skills. It's best to wait at least 6 hours after you take your dose of Xywav to do any activities that need your full attention or coordinated movement.
Risk factors: Personal or family history of alcohol or substance use disorder
Xywav is a schedule III controlled substance. It has a risk for misuse (when a medication is purposefully used for a non-medical reason). Misusing Xywav can raise the risk for serious and possibly life-threatening side effects, such as seizures, dangerously slowed breathing, changes in how alert you are, coma, and death. Misuse can also sometimes lead to addiction.
To lower the risk for misuse and addiction, take Xywav exactly as prescribed. Don't change the dose or how often you take it without talking to the prescriber first. Speak with your care team if you're concerned about this risk.
Because of the risks for misuse, extreme sleepiness, and slowed breathing, the FDA has required Xywav to be distributed through a Risk Evaluation and Mitigation Strategy (REMS) program called the Xywav REMS Program. You, your prescriber, and the pharmacy must all enroll in this program to make sure that you're taking this medication safely. Under the Xywav REMS program, your prescriber will discuss with you about how to safely and responsibly store, use, and dispose of Xywav.
Risk factors: Long-term use of Xywav
In studies, some people who suddenly stopped taking Xywav reported having anxiety, difficulty sleeping, and hallucinations (seeing or hearing things that aren't real). These could be signs of withdrawal, which can happen when you suddenly stop taking a medication after you've become physically dependent on it (when your body relies on the medication to function, typically with long-term use). Some cases of withdrawal occurred with recommended doses of Xywav, so it's important to be aware of this risk. Other possible withdrawal symptoms can include nausea, tremor, sweating, racing heartbeat, and muscle aches. To lower the risk for withdrawal, speak with your prescriber before you stop Xywav or lower your dose about how to do so safely.
Risk factors: History of mental health conditions
Some people who take Xywav have had symptoms of depression, suicidal thoughts, and other mental health problems. Contact your prescriber if you experience any depression (e.g., feelings of guilt, worthlessness), confusion, anxiety, hallucinations (seeing or hearing things that aren't real), paranoia, or unusual or disturbing thoughts. Get medical help right away if you have thoughts of harming yourself.
Xywav might cause unusual sleep behaviors (or parasomnias), including sleepwalking. This can raise your risk of injuring yourself. Make sure your family and loved ones know about this side effect so they can watch out for your safety. Tell your prescriber if you have sleepwalking episodes or if you wander throughout the night.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Works well to prevent cataplexy attacks during the day in people with narcolepsy
Works well to lessen daytime sleepiness in adults with idiopathic hypersomnia
Can use in children as young as 7 years old with narcolepsy
Comes as a liquid that's stored at room temperature, so easy to keep next to your bed
Has 92% less sodium than Xyrem (sodium oxybate), so might be a better choice for people who need to follow a low-salt diet
Is a controlled substance because of the risk of misuse and dependence
Can cause most people to fall asleep within 5 to 15 minutes, so must be ready for bed when you take it
Has to be mixed with water and taken at least 2 hours after food
Can affect your mood and behavior
Have to wake up in the middle of the night to take the medication if you're taking it twice per night
Take Xywav at least 2 hours after eating. Food can lower the amount of Xywav that gets absorbed into your body. This means the medication might not work as well to treat your condition.
Most people fall asleep about 5 to 15 minutes after taking their Xywav dose. Make sure you're in bed when you take your dose just in case you suddenly fall asleep afterwards. Avoid getting out of bed after you take your dose; otherwise, you might fall and hurt yourself.
You must prepare the Xywav dose(s) before you take the medication. Xywav is a liquid that contains 0.5 grams of medication per 1 mL. After you draw up your dose, you'll need to mix it with water. Make sure you know what your dose is and how much water to mix it with to avoid accidentally taking too much. Ask the prescriber if you're not sure.
If you're prescribed to take Xywav twice per night, prepare both doses every night before going to sleep so they're both ready when you need to take them. Take the second dose of the night 2.5 to 4 hours after the first dose. Set an alarm to wake up for your second dose if you fall asleep. If you miss your second dose, skip it and continue your regular schedule the next night. Don't take two doses of Xywav at one time because it can cause serious side effects.
How to prepare your Xywav dose: Draw up your prescribed dose using the provided syringe. Transfer the medication from the syringe into a clean, empty container provided by the pharmacy. Then, measure about 1/4 cup (60 mL) of water, pour into the container, and mix the medication with the water.
Take your prepared dose(s) of Xywav within 24 hours. Empty the prepared mixture of medication down the sink drain if it's been more than 24 hours and you still haven't taken it.
Don't drive or do anything that requires concentration within 6 hours of taking Xywav. This medication can make you suddenly sleepy or dizzy.
Also, don't drink alcohol or take other sedatives with Xywav. Drinking alcohol or taking other sedatives with this medication can be dangerous because it can cause side effects like sleepiness and dizziness to be more intense.
Let your prescriber or care team know if you have any mood or behavior changes (e.g., depression, anxiety) or have unusual sleep behaviors (e.g., sleepwalking) at any time while you're taking Xywav. You might need to have your dose adjusted or be switched to a different medication.
Make sure to tell your prescriber and pharmacist about all the medications you take and plan to take with Xywav. They can check to make sure all your medications are safe to take together.
Tell your prescriber if you're pregnant, planning to become pregnant, or breastfeeding. It's not clear how safe Xywav is for your baby.
Narcolepsy:
Ages 18 years and older: The typical starting dose is 2.25 grams by mouth at bedtime and 2.25 grams taken 2.5 to 4 hours later. Your prescriber will raise your dose every week to the recommended dose of 6 to 9 grams per night, split into two doses (one time at bedtime and again 2.5 to 4 hours later).
Ages 7 to under 18 years old: The dose will depend on body weight. The dose is taken by mouth twice per night (once at bedtime and again 2.5 to 4 hours later). Your child will first start at a low dose. Then, your child's prescriber will raise the dose every week to a maximum dose of 6 to 9 grams per night.
Idiopathic hypersomnia (IH):
Ages 18 years and older: The dose depends on whether you're taking Xywav once or twice per night.
Once per night: The typical starting dose is up to 3 grams by mouth once every night. Your prescriber will raise your dose every week to the recommended dose of 6 grams per night.
Twice per night: The typical starting dose is up to 2.25 grams by mouth twice every night (once at bedtime and then again 2.5 to 4 hours later). Your prescriber will raise your dose every week to the recommended dose of 9 grams per night, split into two doses (one time at bedtime and again 2.5 to 4 hours later).
Your dose might differ if you have liver problems or if you're currently taking divalproex (Depakote).
Take other sedative hypnotics (e.g., sleep medications)
Drink alcohol
A rare condition called succinic semialdehyde dehydrogenase deficiency
Cataplexy (sudden muscle weakness) or excessive daytime sleepiness (EDS) in people ages 7 years and older with narcolepsy
Idiopathic hypersomnia (IH) in adults
Excessive daytime sleepiness or cataplexy (sudden muscle weakness) in adults with narcolepsy
Excessive daytime sleepiness in children ages 6 and older with narcolepsy
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Bogan, R. K., et al. (2021). Efficacy and safety of calcium, magnesium, potassium, and sodium oxybates (lower-sodium oxybate [LXB]; JZP-258) in a placebo-controlled, double-blind, randomized withdrawal study in adults with narcolepsy with cataplexy. Sleep.
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Jazz Pharmaceuticals, Inc. (2023). Xywav (- calcium, magnesium, potassium, and sodium oxybates solution [package insert]. DailyMed.
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