Calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate
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From MedlinePlus, U.S. National Library of Medicine
Boxed warning
WARNING: CENTRAL NERVOUS SYSTEM DEPRESSION and ABUSE AND MISUSE. • Central Nervous System Depression XYWAV is a CNS depressant. Clinically significant respiratory depression and obtundation may occur in patients treated with XYWAV at recommended doses [see Warnings and Precautions ( 5.1 , 5.4 )]. Many patients who received XYWAV during clinical trials in narcolepsy and idiopathic hypersomnia were receiving central nervous system stimulants [see Clinical Studies ( 14.1 , 14.2 , 14.3 )]. • Abuse and Misuse The active moiety of XYWAV is oxybate or gamma-hydroxybutyrate (GHB).
Abuse or misuse of illicit GHB, either alone or in combination with other CNS depressants, is associated with CNS adverse reactions, including seizure, respiratory depression, decreases in the level of consciousness, coma, and death [see Warnings and Precautions ( 5.2 )]. Because of the risks of CNS depression and abuse and misuse, XYWAV is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the XYWAV and XYREM REMS [see Warnings and Precautions ( 5.3 )]. WARNING: CENTRAL NERVOUS SYSTEM (CNS) DEPRESSION and ABUSE AND MISUSE. See full prescribing information for complete boxed warning.
Central Nervous System Depression • XYWAV is a CNS depressant, and respiratory depression can occur with XYWAV use ( 5.1 , 5.4 ) Abuse and Misuse • The active moiety of XYWAV is oxybate or gamma-hydroxybutyrate (GHB). Abuse or misuse of illicit GHB is associated with CNS adverse reactions, including seizure, respiratory depression, decreased consciousness, coma, and death ( 5.2 , 9.2 ) XYWAV is available only through a restricted program called the XYWAV and XYREM REMS ( 5.3 )
Handling and access
REMS
RequiredStated in the label quoted on this page.
- Restricted distribution (ETASU)
- Medication Guide
Dosing in kidney impairment
This label has no separate kidney-impairment dosing section. Check warnings and clinical pharmacology in the full label.
Dosing in liver impairment
Dosage Modification in Patients with Hepatic Impairment The recommended starting dosage in patients with hepatic impairment is one-half of the original dosage per night administered orally, divided into two doses [see Use in Specific Populations and Clinical Pharmacology] .
Preparation and administration
Important Administration Instructions for All Patients Administer XYWAV at least 2 hours after eating [see Clinical Pharmacology] . Prepare all doses of XYWAV prior to bedtime. Prior to ingestion, each dose of XYWAV should be diluted with approximately ¼ cup (approximately 60 mL) of water in the empty pharmacy-provided containers.
Solutions prepared following dilution should be consumed within 24 hours. Patients should take each dose of XYWAV while in bed and lie down immediately after dosing, and remain in bed following ingestion of each dose. XYWAV may cause patients to fall asleep abruptly without first feeling drowsy [see Adverse Reactions] .
Patients will often fall asleep within 5 minutes of taking XYWAV, and will usually fall asleep within 15 minutes, though the time it takes any individual patient to fall asleep may vary from night to night. If dosing twice nightly, patients may need to set an alarm to awaken for the second dose. If the second dose is missed, that dose should be skipped and XYWAV should not be taken again until the next night.
Two XYWAV doses should never be taken at one time.
Dosage Adjustment with Co-administration of Divalproex Sodium When initiating divalproex sodium in patients taking a stable dosage of XYWAV, a reduction of the XYWAV dosage by at least 20% is recommended with initial concomitant use [see Drug Interactions and Clinical Pharmacology] . When initiating XYWAV in patients already taking divalproex sodium, a lower starting dosage of XYWAV is recommended.
Subsequently, the dosage of XYWAV can be adjusted based on individual clinical response and tolerability.
Drug interactions
Check calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate against a medication listLabel text (3 paragraphs)
7 DRUG INTERACTIONS • Concomitant use with divalproex sodium: An initial reduction in XYWAV dose of at least 20% is recommended ( 2.7 , 7.2 ).
7.1 Alcohol, Sedative Hypnotics, and CNS Depressants XYWAV is contraindicated for use in combination with alcohol or sedative hypnotics. Use of other CNS depressants may potentiate the CNS-depressant effects of XYWAV [see Warnings and Precautions ( 5.1 )] .
7.2 Divalproex Sodium Concomitant use of sodium oxybate with divalproex sodium results in an increase in systemic exposure to GHB, which was shown to cause a greater impairment on some tests of attention and working memory in a clinical study [see Clinical Pharmacology ( 12.3 )] . A similar increase in exposure is expected with concomitant use of XYWAV and divalproex sodium; therefore, an initial dose reduction of XYWAV is recommended when used concomitantly with divalproex sodium [see Dosage and Administration ( 2.7 )]. Prescribers are advised to monitor patient response closely and adjust dose accordingly if concomitant use of XYWAV and divalproex sodium is warranted.
Contraindications
4 CONTRAINDICATIONS XYWAV is contraindicated for use in: • combination with sedative hypnotics [see Warnings and Precautions ( 5.1 )] . • combination with alcohol [see Warnings and Precautions ( 5.1 , 5.2 )] . • patients with succinic semialdehyde dehydrogenase deficiency [see Clinical Pharmacology ( 12.3 )] . • In combination with sedative hypnotics or alcohol ( 4 ) • Succinic semialdehyde dehydrogenase deficiency ( 4 )
Safety data
Reported adverse events (FAERS)
Liver injury (LiverTox)
LiverTox has no chapter for calcium oxybate, magnesium oxybate, potassium oxybate, and sodium oxybate. Check the label's hepatic warnings.
Pregnancy and lactation
Pregnancy
8.1 Pregnancy Risk Summary There are no adequate data on the developmental risk associated with the use of XYWAV or sodium oxybate in pregnant women. Oral administration of sodium oxybate to pregnant rats (0, 150, 350, or 1,000 mg/kg/day) or rabbits (0, 300, 600, or 1,200 mg/kg/day) throughout organogenesis produced no clear evidence of developmental toxicity; however, oral administration to rats throughout pregnancy and lactation resulted in increased stillbirths and decreased offspring postnatal viability and growth, at a clinically relevant dose [see Data] . In the U.S.
general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 15-20%, respectively. The background risk of major birth defects and miscarriage for the indicated population is unknown. Clinical Considerations Labor or Delivery XYWAV has not been studied in labor or delivery. In obstetric anesthesia using an injectable formulation of sodium oxybate, newborns had stable cardiovascular and respiratory measures but were very sleepy, causing a slight decrease in Apgar scores. There was a fall in the rate of uterine contractions 20 minutes after injection.
Placental transfer is rapid, and gamma-hydroxybutyrate (GHB) has been detected in newborns at delivery after intravenous administration of GHB to mothers. Subsequent effects of sodium oxybate on later growth, development, and maturation in humans are unknown. Data Animal Data Oral administration of sodium oxybate to pregnant rats (0, 150, 350, or 1,000 mg/kg/day) or rabbits (0, 300, 600, or 1,200 mg/kg/day) throughout organogenesis produced no clear evidence of developmental toxicity. The highest doses of sodium oxybate tested in rats and rabbits were approximately 1 and 3 times, respectively, the maximum recommended human dose (MRHD) of 9 g per night on a body surface area (mg/m 2 ) basis.
Additionally, oral administration of sodium oxybate (0, 150, 350, or 1,000 mg/kg/day) to rats throughout pregnancy and lactation resulted in increased stillbirths and decreased offspring postnatal viability and body weight gain at the highest dose tested. The no-effect dose for pre- and post-natal developmental toxicity in rats is less than the MRHD on a mg/m 2 basis.
For breastfeeding, also see LactMed (National Library of Medicine), which summarizes milk levels and infant effects.
Supply and cost
Drug shortage status
Recalls (last 24 months)
Therapeutic equivalence (Orange Book)
Price ladder
Not the price at the counterThese are not what a patient pays at the pharmacy counter. They are what pharmacies, health plans, and government buyers pay, before manufacturer rebates. A patient's cost depends on their insurance (copay, coinsurance, or deductible) or the pharmacy's cash price.