Xyrem (sodium oxybate) is a prescription drug used to treat certain narcolepsy symptoms. Xyrem can cause side effects that range from mild to serious. Examples include sleepiness, dizziness, and changes in mental health.

Specifically, Xyrem is used in adults and certain children to treat the following narcolepsy symptoms:

Xyrem comes as an oral liquid solution. It contains the active ingredient sodium oxybate.

Keep reading to learn about common, mild, and serious side effects Xyrem can cause. For a general overview of the drug, including details about its uses, see this article.

Xyrem has boxed warnings. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For details, see the “Side effects explained” section.

Some people may experience mild to serious side effects during Xyrem treatment. Examples of the drug’s commonly reported side effects include:

Mild side effects have been reported with Xyrem. These include:

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bothersome, talk with your doctor or pharmacist. And do not stop Xyrem treatment unless your doctor recommends it.

Xyrem may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

Serious side effects have been reported with Xyrem. These include:

If you develop serious side effects while taking Xyrem, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

* To learn more about this side effect, see the “Side effects explained” section.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Xyrem, visit MedWatch.

Allergic reaction

For some people, Xyrem can cause an allergic reaction. But this side effect wasn’t reported in the drug’s studies.

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms and can determine whether you should continue Xyrem treatment.

If you have symptoms of a severe allergic reaction, such as swelling or difficulty breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Xyrem, they may have you switch to a different treatment.

Get answers to some frequently asked questions about Xyrem’s side effects.

Are there any long-term side effects of Xyrem?

Long-term side effects from Xyrem are possible, but rare. Most side effects of this drug are expected to be temporary and should go away soon after starting or stopping it.

However, certain side effects of Xyrem may have a longer-lasting impact. This includes changes in mental health* such as depression or suicidal thoughts and actions.

Talk with your doctor to learn more about possible side effects of Xyrem and how long they may last.

* To learn more about this side effect, see the “Side effects explained” section.

How do side effects of Xyrem in children compare with those seen in adults?

Most Xyrem side effects are similar in children and adults. (See examples listed in the “What are the mild side effects of Xyrem?” and “What are the serious side effects of Xyrem?” sections.)

However, in studies, other side effects were reported in children that weren’t reported in adults. These include:

  • headache
  • loss of appetite
  • weight loss

For more information about possible side effects of Xyrem in children, talk with your child’s doctor or a pharmacist.

Keeping track of side effects

During your Xyrem treatment, consider taking notes on any side effects you’re having. You can then share this information with your doctor. This is especially helpful when you first start a new drug or combination of treatments.

Your side effect notes can include things such as:

  • what dose of the drug you were taking when you had the side effect
  • how soon you had the side effect after starting that dose
  • what your symptoms were
  • how your symptoms affected your daily activities
  • what other medications you were taking
  • any other information you feel is important

Sharing notes with your doctor will help them learn more about how Xyrem affects you. They can then use this information to adjust your treatment plan if needed.

Learn more about some of the side effects Xyrem may cause.

Boxed warning: Risk of central nervous system (CNS) depression

Xyrem has a boxed warning about the risk of CNS depression. A boxed warning is the most serious warning from the FDA. It alerts doctors and patients about drug effects that may be dangerous.

CNS depression was an uncommon side effect reported in studies of Xyrem. With CNS depression, the activity of your CNS (brain and spinal cord) is slowed. This affects functions in your body such as thinking, movement, and breathing.

CNS depression may cause symptoms such as:

In extreme cases, CNS depression may be fatal.

Certain factors can increase the risk of CNS depression when taking this drug. These include drinking alcohol and taking other medications that cause CNS depression. Examples include sedatives and benzodiazepines.

What might help

Due to the risk of CNS depression, Xyrem is available only through the Xywav and Xyrem risk evaluation and mitigation strategy (REMS) program. The FDA requires this program for certain drugs to help make sure they’re safely prescribed.

It’s important to avoid operating machinery or driving a vehicle until you know how Xyrem may affect you. Your doctor will likely advise you to avoid these activities for at least 6 hours after taking the drug. (Keep in mind that Xyrem is taken at bedtime before going to sleep.)

If you have symptoms of CNS depression during Xyrem treatment, talk with your doctor right away. But if your symptoms seem severe or life threatening, call 911 or a local emergency number. Your doctor will recommend ways to manage your symptoms and determine whether it’s safe for you to continue Xyrem treatment.

Boxed warning: Risk of misuse

Xyrem has a boxed warning about the risk of misuse. A boxed warning is the most serious warning from the FDA. It alerts doctors and patients about drug effects that may be dangerous.

With misuse, a drug is taken in a way other than how a doctor prescribes it. While misuse wasn’t reported in Xyrem studies, it is a known risk of drugs similar to Xyrem. Because of this, Xyrem is categorized as a Schedule III controlled substance. This means the drug has an approved medical use but may be misused for other purposes. It also means government agencies, doctors, and pharmacists pay close attention to how it’s prescribed and used.

Misuse may cause symptoms such as:

In extreme cases, misuse of Xyrem may lead to coma or death.

Certain factors can increase the risk of misuse when taking Xyrem, including ever having a substance use disorder. Taking Xyrem more often or at higher doses than prescribed by your doctor may also increase this risk.

What might help

Due to the risk of misuse, Xyrem is available only through the Xywav and Xyrem REMS program. The FDA requires this program for certain drugs to help make sure they’re safely prescribed.

During your Xyrem treatment, your doctor will monitor you for signs of misuse. They’ll recommend whether Xyrem is the right treatment option.

Changes in mental health

Changes in mental health were reported in studies of Xyrem. Depression, anxiety, and confusion were among the more commonly reported changes in mental health.

Less commonly reported changes in mental health include:

Certain factors may increase the risk of mental health changes when taking this drug. These include taking high doses of Xyrem or ever having a mental health condition.

What might help

If you have mental health changes during Xyrem treatment, talk with your doctor right away. They’ll recommend whether it’s safe for you to keep taking the drug. They can also advise you on ways to manage your symptoms.

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

  • Call or text the 988 Suicide and Crisis Lifeline at 988 or chat at 988lifeline.org. Caring counselors are available to listen and provide free and confidential support 24/7.
  • Text HOME to the Crisis Text Line at 741741 to connect with a volunteer crisis counselor for free and confidential support 24/7.
  • Not in the United States? Find a helpline in your country with Befrienders Worldwide.
  • Call 911 or your local emergency services number if you feel safe to do so.

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you’re not in the same household, stay on the phone with them until help arrives.

Below is important information you should consider before starting Xyrem.

Boxed warning: Risks of CNS depression and misuse

Xyrem has boxed warnings. A boxed warning is the most serious warning from the FDA. For details, see the “Side effects explained” section.

Other warnings

Xyrem can sometimes cause harmful effects in people with certain conditions. This is known as a drug-condition interaction. Other factors may also affect whether Xyrem is a good treatment option for you.

Talk with your doctor about your health history before starting this medication. Be sure to tell them if any of the following factors apply to you:

  • low sodium diet
  • liver problems
  • kidney problems
  • heart failure
  • high blood pressure
  • breathing problems, including sleep apnea
  • mental health conditions, including anxiety or depression
  • succinic semialdehyde dehydrogenase deficiency, an inherited condition that can affect how your body breaks down Xyrem
  • previous allergic reaction to Xyrem
  • pregnancy
  • breastfeeding
  • alcohol consumption

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.