Calcium, Magnesium, Potassium, and Sodium Oxybate
Calcium, magnesium, potassium, and sodium oxybate is a CNS depressant used to treat cataplexy and excessive daytime sleepiness in narcolepsy, and to treat idiopathic hypersomnia (a condition of excessive, hard-to-shake sleepiness) in adults.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 1 clinical label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
⚠️ FDA Boxed Warning — the FDA’s strongest safety alert ▾
Xywav carries two serious black-box warnings from the FDA.
First, it is a central nervous system (CNS) depressant — meaning it slows brain activity, including the drive to breathe. Dangerous respiratory depression (slowed or stopped breathing) can occur even at normal prescribed doses. This risk is greatly increased if Xywav is combined with alcohol, sedative sleep aids, opioids, or other CNS depressants. Watch for signs like very slow or shallow breathing, extreme sedation, or inability to wake someone up — these are emergencies requiring immediate medical attention.
Second, the active ingredient in Xywav is oxybate, also known as GHB — a substance that has been abused illicitly. Abuse of GHB has caused seizures, respiratory depression, coma, and death. Because of these serious risks, Xywav is only available through a restricted safety program called the XYWAV and XYREM REMS. It can only be dispensed by a specially certified central pharmacy to patients enrolled in this program.
📖 Calcium, Magnesium, Potassium, and Sodium Oxybate: Patient Information Guide
A plain-language walkthrough of Calcium, Magnesium, Potassium, and Sodium Oxybate — what it treats, how it works, how it’s taken, side effects, warnings and interactions. Tap any section to expand it.
🎯What it's used for▾
Xywav (calcium, magnesium, potassium, and sodium oxybate) is a CNS depressant approved for two distinct sleep-related conditions:
- Narcolepsy: Xywav is approved to treat cataplexy (sudden episodes of muscle weakness) and excessive daytime sleepiness (EDS) in patients 7 years of age and older with narcolepsy.
- Idiopathic hypersomnia (IH): Xywav is approved to treat this condition — characterized by excessive, difficult-to-overcome sleepiness despite adequate sleep — in adults only. Xywav is not approved for idiopathic hypersomnia in patients under 18.
⚙️How it works▾
Xywav's active ingredient is oxybate — the same compound as gamma-hydroxybutyrate (GHB), which the body produces naturally as a byproduct of GABA, the brain's main calming neurotransmitter. The exact mechanism isn't fully understood, but researchers believe oxybate works through GABA-B receptors active during sleep in brain regions that regulate noradrenaline and dopamine — two chemicals tied to alertness and muscle control. By acting on these pathways during nighttime sleep, it is thought to consolidate and improve sleep quality in ways that reduce daytime sleepiness and cataplexy episodes.
💊How it's taken▾
Xywav is an oral liquid solution taken at night. It must be taken at least 2 hours after the last meal, because eating substantially reduces how much of the drug reaches your bloodstream. Before going to bed, prepare your dose(s) by mixing with about ¼ cup of water in the special containers provided by the pharmacy.
- For narcolepsy (adults and children 7+): Xywav is taken twice per night — the first dose at bedtime and the second dose 2.5 to 4 hours later. Take each dose while already lying in bed.
- For idiopathic hypersomnia (adults): Xywav can be prescribed as either a once-nightly or twice-nightly regimen depending on your prescriber's guidance.
- If you are switching from Xyrem to Xywav, you can start at the same dose and schedule (gram for gram), adjusting as needed with your prescriber.
If you have liver disease, your starting dose will be lower. Never change your dose on your own — always follow your prescriber's instructions.
🤒Side effects — in detail▾
Like most CNS depressants, Xywav most commonly causes side effects during the first few weeks of treatment, and many improve over time.
- Nausea
- Headache
- Dizziness
- Decreased appetite
- Anxiety
- Excessive sweating or night sweats
- Vomiting or diarrhea
- Dry mouth
- Parasomnias (abnormal sleep behaviors such as sleepwalking, sleep talking, or sleep terrors)
- Fatigue
- Tremor
- Insomnia (reported particularly in idiopathic hypersomnia patients)
Seek immediate medical help if you experience very slow or difficult breathing, prolonged unconsciousness, or severe confusion. Contact your prescriber promptly for new or worsening depression, suicidal thoughts, sleepwalking, or significant mood or behavior changes.
⚠️Warnings & precautions▾
- Breathing depression: Xywav can dangerously slow breathing even at recommended doses. This risk is greatly magnified by alcohol, sedative sleep aids, opioids, benzodiazepines, or other CNS depressants — combinations that can be fatal.
- Abuse and misuse risk: The active ingredient GHB is a controlled substance with serious misuse potential. Signs of misuse — such as taking larger or more frequent doses, or drug-seeking behavior — should be reported to a prescriber immediately.
- REMS program: Xywav is only dispensed through a specially certified pharmacy under the XYWAV and XYREM REMS restricted safety program.
- Depression and suicidality: Cases of depression and suicidal thoughts have occurred in patients on Xywav. Prescribers should monitor patients closely, especially early in treatment.
- Sleep-disordered breathing: Xywav may worsen sleep apnea or cause central apneas (pauses in breathing during sleep). Patients with pre-existing breathing disorders need especially close monitoring.
- Sleepwalking and parasomnias: Sleepwalking and other abnormal sleep behaviors have been reported; falls and injuries have resulted.
- Driving and machinery: Do not drive or engage in any activity requiring full alertness for at least 6 hours after a dose.
🔀What it interacts with▾
Xywav interacts with several substances that affect the brain or breathing — some combinations are strictly forbidden:
- Alcohol: Absolutely contraindicated. Combining with Xywav can cause life-threatening respiratory depression, loss of consciousness, coma, or death.
- Sedative hypnotics (sleep aids): Contraindicated. The combination dramatically worsens CNS and respiratory depression.
- Other CNS depressants (opioids, benzodiazepines, sedating antidepressants or antipsychotics, muscle relaxants, general anesthetics): Concurrent use is not recommended; if unavoidable, dose reductions and close monitoring are required.
- Divalproex sodium (valproate): Increases the amount of Xywav in the bloodstream, which can worsen attention and memory. An initial Xywav dose reduction of at least 20% is recommended if used together, with close monitoring.
This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.
📋Before taking it▾
- Do not take Xywav if you also take sedative hypnotics (sleep aids) or drink alcohol.
- Do not take Xywav if you have succinic semialdehyde dehydrogenase deficiency (a rare inherited metabolic disorder) — Xywav cannot be safely broken down in your body.
- Tell your doctor about any liver disease — your starting dose must be reduced by half, as the drug builds up more in people with liver problems.
- Tell your doctor if you have breathing problems, sleep apnea, or are overweight, as these increase the risk of breathing complications.
- Tell your doctor if you have a personal or family history of depression, suicidal thinking, or psychiatric illness.
- Tell your doctor if you have a history of substance abuse — Xywav has significant misuse potential.
- Pregnancy: Animal studies suggest Xywav may harm an unborn baby. If you are pregnant or planning to become pregnant, discuss this carefully with your doctor.
- Breastfeeding: GHB passes into human breast milk. Talk with your doctor about the risks and benefits before breastfeeding.
- Children under 7: Xywav for narcolepsy is not approved for children younger than 7. It is not approved for idiopathic hypersomnia in anyone under 18.
- Older adults: Use with extra caution; elderly patients are at higher risk for impaired thinking, balance problems, and falls. Start at the lowest dose.
🚑If you take too much▾
Taking too much Xywav (or GHB) can cause rapidly shifting states of confusion and agitation, followed by deep unconsciousness, very slow or stopped breathing, seizures, slowed heart rate, and low body temperature. If an overdose is suspected, call 911 immediately and contact Poison Control at 1-800-222-1222. There is no specific antidote — treatment is supportive, focused on protecting the airway and breathing.
🔬Pharmacokinetics — how your body processes it▾
After you take Xywav by mouth, it is absorbed relatively quickly — blood levels typically peak in about 1.3 hours when taken on an empty stomach. Eating a high-fat meal before your dose significantly reduces absorption, which is why Xywav must be taken at least 2 hours after food. The drug is processed almost entirely by the body's own enzymes (converted to carbon dioxide and water), with less than 5% leaving the body unchanged in urine. The elimination half-life — how long it takes for half the drug to be cleared — is very short, averaging less than one hour, which is why the second nightly dose is needed. In people with liver disease (cirrhosis), the drug stays in the body much longer and reaches higher levels, requiring a lower starting dose.
📦How to store it▾
Keep out of reach of children. stored between 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C (59°F and 86°F) (see USP Controlled Room Temperature). Dispense in tight containers.
📄 Written from Calcium, Magnesium, Potassium, and Sodium Oxybate’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Every point is grounded in that labeling — nothing is invented. How we use AI →
Supplements & herbs that interact with Calcium, Magnesium, Potassium, and Sodium Oxybate
23 supplements and herbal products have documented interactions with Calcium, Magnesium, Potassium, and Sodium Oxybate in the licensed clinical database we use. Most are manageable — but your pharmacist should know about everything you take, including vitamins and herbals.
- Major · 1
- Moderate · 13
- Minor · 9
Educational information from a licensed clinical database (Natural Medicines) — see our data sources & update cadence. Not medical advice: an interaction being documented does not mean it will happen to you; do not start or stop medications or supplements without professional guidance.
🩺 Pharmacist Counseling Corner
Quick, plain-English answers to the questions patients ask most about Calcium, Magnesium, Potassium, and Sodium Oxybate — the kind of thing our pharmacy team would talk through with you at the counter.
Why do I have to take this medicine in the middle of the night? Can't I just take it all at once before bed? ▾
Is it really that important not to eat before taking it? ▾
I've heard GHB is a dangerous street drug. Is this the same thing? ▾
Can I have a glass of wine with dinner if I take my Xywav a couple of hours later? ▾
What side effects should I actually expect, especially when I'm just starting? ▾
Is it safe to take Xywav with my other medications? ▾
Is Calcium, Magnesium, Potassium, and Sodium Oxybate available over the counter? ▾
Is Calcium, Magnesium, Potassium, and Sodium Oxybate a controlled substance? ▾
When was Calcium, Magnesium, Potassium, and Sodium Oxybate first available? ▾
💬 Answers drafted from Calcium, Magnesium, Potassium, and Sodium Oxybate’s FDA-approved label information, summarized in plain language with AI, and reviewed by our pharmacy team before publication. Grounded in that labeling — nothing is made up. How we use AI →
🧰 Keep exploring
💊 How Calcium, Magnesium, Potassium, and Sodium Oxybate comes
Calcium, Magnesium, Potassium, and Sodium Oxybate is available in 1 form. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Oral solution
How this form is used
- Xywav oral solution is used to treat cataplexy or excessive daytime sleepiness in patients 7 years of age and older with narcolepsy
- Xywav oral solution is used to treat idiopathic hypersomnia in adults
- Xywav must be taken at least 2 hours after eating; food significantly reduces absorption
- Xywav doses are diluted with approximately ¼ cup of water in the pharmacy-provided containers before taking
- Xywav should be taken while already in bed; lie down immediately after each dose
- Xywav is typically taken in two doses per night, with the second dose taken 2.5 to 4 hours after the first; for idiopathic hypersomnia in adults, a once-nightly regimen is also an option
📊 Calcium, Magnesium, Potassium, and Sodium Oxybate across the U.S. market
How Calcium, Magnesium, Potassium, and Sodium Oxybate appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
📈 How widely Calcium, Magnesium, Potassium, and Sodium Oxybate is used
A general measure of how commonly Calcium, Magnesium, Potassium, and Sodium Oxybate is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Calcium, Magnesium, Potassium, and Sodium Oxybate is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Calcium, Magnesium, Potassium, and Sodium Oxybate prescribed? Of the 1,594 medications we measure, Calcium, Magnesium, Potassium, and Sodium Oxybate ranks #944 by Medicaid prescriptions — more than 41% of them.
Utilization by Calcium, Magnesium, Potassium, and Sodium Oxybate product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
calcium oxybate 234 MG/ML / magnesium oxybate 96 MG/ML / potassium oxybate 130 MG/ML / sodium oxybate 40 MG/ML Oral Solution
Summed across the 1 of 1 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 2393795
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Calcium, Magnesium, Potassium, and Sodium Oxybate, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 1 of 1 listed Calcium, Magnesium, Potassium, and Sodium Oxybate NDCs with Medicaid activity.
🔍 Compare Calcium, Magnesium, Potassium, and Sodium Oxybate products
A representative set of FDA-listed product records for Calcium, Magnesium, Potassium, and Sodium Oxybate — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Oral solution | ||||
| SODIUM OXYBATE 0.5 g/mL; CALCIUM OXYBATE 0.5 g/mL; POTASSIUM OXYBATE 0.5 g/mL; MAGNESIUM OXYBATE 0.5 g/mL | Oral | Jazz Pharmaceuticals, Inc. | NDA | View NDC → |
Showing 1 of 1 products — FDA National Drug Code Directory. See every product, package size and price: browse all 1 Calcium, Magnesium, Potassium, and Sodium Oxybate NDCs →
📈 What people report — real-world data (FDA FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Calcium, Magnesium, Potassium, and Sodium Oxybate — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Calcium, Magnesium, Potassium, and Sodium Oxybate in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
🏛️ The road to your pharmacy
How Calcium, Magnesium, Potassium, and Sodium Oxybate went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
🚨 Recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
Source: openFDA drug enforcement (recall) reports.
📦 Supply & shortage status
Whether Calcium, Magnesium, Potassium, and Sodium Oxybate is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
🏷️ Sold under these brand names
🏭 Manufacturers & labelers
RxNorm drug class
Calcium, Magnesium, Potassium, and Sodium Oxybate belongs to the Other general anesthetics class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
🔬 Where this comes from
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How we combine label and product data
HelloPharmacist combines public FDA and NLM records; we don’t author the underlying clinical facts. We identified 1 FDA-filed SPL label set within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. The representative label is the starting point for the displayed reference monograph; the 12 largest stored in-scope SPL records, which may include that representative, are compared section by section, and the longest available version of each section is retained. Forms, routes, brands, labelers, product-listed strengths, and product-record counts are aggregated separately from ingredient-matched FDA NDC Directory records; package records listed above are associated with the linked SPL; and the normalized concept hierarchy comes from NLM RxNorm.
For canonical ingredient pages, bounded product-attributed indication and administration excerpts may be added to the AI evidence, and the generator is instructed to preserve available product, brand, route, and form qualifiers instead of treating one label as universal. Where a section is identified as AI-written, its plain-language text is generated from bounded label evidence. New draft drug pages remain in the admin review queue before first publication. Jazz Pharmaceuticals, Inc. is the representative DailyMed label linked for verification and dates; it is not the sole source used for the page.
This is general education, not medical advice — always consult your doctor or pharmacist about your medications and any medical condition. For the exact wording of the linked representative label, view that label on DailyMed; some displayed composite sections may come from other in-scope SPL labels. Learn how we use AI and our data sources & update cadence.