Sodium Oxybate (Xyrem)

Xyrem (sodium oxybate) is used to treat cataplexy in narcolepsy.

Excessive Daytime Sleepiness in Narcolepsy

Xyrem (sodium oxybate) is used to treat excessive daytime sleepiness (EDS) in narcolepsy.

What are the side effects of sodium oxybate (Xyrem)?

WARNING

Xyrem (sodium oxybate) is a CNS depressant. In clinical trials, obtundation and respiratory depression occurred with Xyrem. Almost all patients who received Xyrem in narcolepsy trials were taking CNS stimulants.

Xyrem (sodium oxybate) is the sodium salt of gamma hydroxybutyrate (GHB). Abuse of GHB, alone or with other CNS depressants, can cause seizures, respiratory depression, decreased consciousness, coma, and death.

Due to the risks, Xyrem is only available through the Xyrem Success Program. Prescribers and patients must enroll in the program.

For more information go to www.XYREM.com or call 1-866-XYREM88 (1-866-997-3688).

Xyrem can cause serious side effects, including:

• Breathing problems, including slower breathing, trouble breathing, and sleep apnea.

People with existing breathing or lung problems are at higher risk of breathing problems with Xyrem.

• Mental health problems, including confusion, hallucinations, abnormal thinking, anxiety, depression, and thoughts of suicide.

Call your doctor immediately if you have symptoms of mental health problems.

• Sleepwalking, which can cause injuries. Call your doctor if you start sleepwalking.

The most common side effects of Xyrem include:

Your side effects may increase with higher doses of Xyrem. Xyrem can cause physical dependence and craving when not taken as directed. This is not a complete list of the side effects of Xyrem.

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.

Is sodium oxybate (Xyrem) addictive?

Xyrem (sodium oxybate) produces dose-dependent CNS effects, including hypnotic and positive reinforcing effects. It can be abused and misused due to its rapid onset of action.

The sedative effects of Xyrem, especially when combined with alcohol, can be dangerous. Illicit GHB is commonly abused in social settings, particularly by young adults. Severe dependence and craving for GHB can occur with around-the-clock use.

Signs of abuse and dependence include increasing doses, frequent use, and continued use despite adverse consequences.

Physicians should evaluate patients for a history of drug abuse and closely monitor them for signs of GHB misuse or abuse.

What are the withdrawal symptoms for sodium oxybate (Xyrem)?

Withdrawal from illicit use of GHB at high doses can cause symptoms such as insomnia, restlessness, anxiety, psychosis, lethargy, nausea, tremor, sweating, muscle cramps, tachycardia, headache, dizziness, fatigue, sleepiness, confusion, visual hallucinations, agitation, and delirium. These symptoms generally resolve within 3 to 14 days but severe cases may require hospitalization.

In clinical trials, some patients experienced anxiety and insomnia after discontinuing Xyrem at the end of the trial.

QUESTION

What is the dosage for sodium oxybate (Xyrem)?

The recommended starting dose is 4.5 grams (g) per night administered orally in two equal, divided doses: 2.25 g at bedtime and 2.25 g taken 2.5 to 4 hours later. Increase the dose by 1.5 g per night at weekly intervals to achieve a dose range of 6 g to 9 g per night. Doses higher than 9 g per night have not been studied and should not be used.

Take Xyrem on an empty stomach, at least 2 hours after eating. Dilute each dose with approximately 1/4 cup (approximately 60 mL) of water before taking.

Take Xyrem while in bed and lie down immediately after dosing. Xyrem may cause sudden sleep onset without drowsiness. Most patients fall asleep within 5 to 15 minutes of taking Xyrem.

Some patients may take up to 2 hours to fall asleep. Remain in bed after the first dose and wait 2.5 to 4 hours before taking the second dose.

What drugs interact with sodium oxybate (Xyrem)?

Xyrem should not be used with alcohol or sedative hypnotics. Other CNS depressants may enhance the effects of Xyrem.

Is sodium oxybate (Xyrem) safe to take while pregnant or breastfeeding?

Pregnancy category C

Xyrem should only be used during pregnancy if the benefits outweigh the risks. Studies in pregnant animals showed no clear evidence of developmental toxicity.

High doses in animals during pregnancy and lactation resulted in adverse effects on offspring.

Nursing mothers

The excretion of sodium oxybate in human milk is unknown. Exercise caution when administering Xyrem to nursing women.

What else should I know about sodium oxybate (Xyrem)?

How does sodium oxybate (Xyrem) work?

Xyrem is a CNS depressant. Its mechanism of action in narcolepsy treatment is unknown. It is hypothesized that Xyrem’s therapeutic effects on cataplexy and excessive daytime sleepiness are mediated through GABAB actions.

Summary

Xyrem (sodium oxybate) oral solution is used to treat cataplexy and excessive daytime sleepiness in narcolepsy.