FDA Approves GHB Drug, Xywav, to Treat Rare Sleeping Disorder

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Lara Antal / Verywell

Key Takeaways

  • The Food and Drug Administration (FDA) approved Xywav to treat adults with idiopathic hypersomnia, a rare sleep disorder where an individual does not get rest from sleeping.
  • There are no other drugs approved in the United States to treat idiopathic hypersomnia.
  • Xywav will only be available through certified healthcare providers and pharmacies.

On August 12, 2021, the Food and Drug Administration (FDA) approved Xywav to treat a sleep condition called idiopathic hypersomnia. Xywav is made by Jazz Pharmaceuticals of Dublin, Ireland.

The drug was already approved to treat adults and children over the age of 7 years with narcolepsy and cataplexy or excessive daytime sleepiness. This approval marks a new use for the drug.

“Idiopathic hypersomnia is a life-long condition, and the approval of Xywav will be instrumental in providing treatment for symptoms such as excessive sleepiness and difficulty waking, and in effectively managing this debilitating disorder,” Eric Bastings, MD, the deputy director of the Office of Neuroscience at the Center for Drug Evaluation and Research, said in a statement from the FDA.

Bastings added that “a novel indication for Xywav is significant as the FDA has never granted an approval for idiopathic hypersomnia.”

What Is Idiopathic Hypersomnia?

Idiopathic hypersomnia is an uncommon sleep disorder. The symptoms of the condition include extreme and debilitating sleepiness during the day; excessive but unrefreshing sleep, difficulty staying awake and alert during the day; unplanned naps, prolonged difficulty waking up, and confusion when waking up. The cause of idiopathic hypersomnia is not known. Patients with the sleep disorder often report managing daytime sleepiness by using caffeine, prescribed stimulants such as methylphenidate (Ritalin), or antidepressants.

What to Know About Xywav

Xywav is an oral mixture of calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate. Oxybate is another name for gamma-hydroxybutyrate (GHB), which depresses the central nervous system.

GHB is sometimes used illicitly as a “date rape” drug that can easily be slipped into a drink to make someone unconscious.

Oxybate—either in the form of Xywav or Xyrem—had already been approved by the FDA to treat three sleep disorders: narcolepsy, cataplexy, and excessive daytime sleepiness.

Xywav is a different version of GHB than another similar drug named Xyrem, which is also made by Jazz Pharmaceuticals.

Xyrem is approved for the treatment of cataplexy and excessive daytime sleepiness. Each dose of Xyrem contains a large amount of sodium—more than the daily recommended level of sodium in the higher doses. Xywav has far less sodium per dose than Xyrem.

Xywav received FDA approval for the treatment of idiopathic hypersomnia after the agency reviewed the data from a clinical study that included 154 adult patients with the condition.

During the trial, the patients were randomly put into two groups. Some continued taking Xywav, and others were switched to a placebo. Researchers found that patients who were switched to placebo experienced worse sleep and more idiopathic hypersomnia symptoms than the patients who took Xywav.

The FDA gave Xywav Fast Track, Priority Review, and Orphan Drug designations, which speeds up the approval process.

How to Take Xywav

Xywav is a concentrated solution that must be diluted with water. The drug's manufacturer advises patients to take the diluted drug once they are already in bed because it can take effect within five minutes and the onset of sleep can be sudden.

The dosage for Xywav starts at 4.5 grams per night by mouth (orally), divided into one or two doses. The dosage can be raised to 9 grams per night.

If two doses are used, they need to be taken between 2.5 and 4 hours apart. Patients should keep their second dose on their night table and might need to set an alarm to make sure that they wake up to take it on time.

What This Means For You

Xywav has been approved by the FDA to treat adults with idiopathic hypersomnia. However, there are strict rules for prescribing the medication because of the risks it carries. It's also expensive, though most insurance companies will cover at least some of the cost and the drug's manufacturer also has programs for people to get help paying for the medication.

Accessibility and Limitations of Xywav

Oxybate has the potential for physical or psychological dependence; therefore, it is a Schedule III controlled substance.

Patients who abruptly stopped taking Xyrem—another prescription version of oxybate—have reported withdrawal. Symptoms of withdrawal can include, insomnia, anxiety, psychosis, confusion, and more.

Xywav carries the potential for abuse. Since it causes central nervous system depression, the FDA is requiring that it be prescribed and dispensed through a Risk Evaluation and Mitigation Strategy program (REMS).

It can only be prescribed by certified healthcare professionals and dispensed only from certified pharmacies. Xywav will only be available by mail order from approved pharmacies and will not be available in retail pharmacies.

Known Side Effects

Common side effects reported by adults taking Xywav include:

  • Nausea
  • Headache
  • Dizziness
  • Anxiety
  • Insomnia
  • Decreased appetite
  • Excessive sweating
  • Vomiting
  • Diarrhea
  • Dry mouth
  • Fatigue
  • Tremor

In the clinical trial for the drug:

  • 21.4% of patients reported nausea
  • 16.2% reported headaches
  • 11.7% reported dizziness
  • 10.4% reported anxiety
  • 10.4% reported vomiting

Some people taking Xywav have also reported sleep-related side effects, such as abnormal dreams, sleep terrors, sleep talking, sleepwalking, sleep talking, and abnormal dreams, sleep paralysis, and sleep talking.

Xywav can also have more serious side effects like:

  • Breathing problems (including sleep apnea)
  • Mental health side effects (including confusion, hallucinations, thoughts of suicide, anxiety, depression, and abnormal thinking)
  • Sleepwalking (which can place a person at risk for injury)

Xywav depresses the central nervous system. It has the potential to slow breathing rate and lower blood pressure—possibly to dangerously low levels. Therefore, Xywav should not be taken with alcohol or any drugs that also depress the central nervous system, such as antidepressants, antipsychotics, benzodiazepines, or opioids.

Getting Xywav to Treat Your Idiopathic Hypersomnia

Oxybate can cause physical dependence. It is also a drug that can be abused, which means that there are special requirements for Xywav prescriptions.

If you think that you might have idiopathic hypersomnia, ask your doctor for a referral to a sleep specialist. They might ask you to keep a sleep diary and have an overnight test in a sleep laboratory.

Only certain doctors are allowed to prescribe Xywav. You will have to obtain the drug by mail order from certified pharmacies.

The out-of-pocket cost for Xywav is about $100,000 a year, according to a report by The New York Times. Most health insurance companies will cover Xywav, but you may have a high copayment. However, there are programs available to help with the cost of Xywav.

9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration (FDA). FDA Grants First of its Kind Indication for Chronic Sleep Disorder Treatment.

  2. Jazz Pharmaceuticals. Xywav FAQs.

  3. U.S. Department of Justice. Drug Enforcement Administration. Gamma hydroxybutyric acid.

  4. Jazz Pharmaceuticals. Transitioning from Xyrem.

  5. Jazz Pharmaceuticals. How to Prepare and Take Xywav.

  6. Food and Drug Administration (FDA). XYWAV: Highlights of Prescribing Information.

  7. Jazz Pharmaceuticals. Xywav Medication Guide.

  8. Jazz Pharmaceuticals. Xywav.

  9. Jazz Pharmaceuticals. How to Get Xywav.

By Valerie DeBenedette
Valerie DeBenedette has over 30 years' experience writing about health and medicine. She is the former managing editor of Drug Topics magazine.