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URL of this page: https://medlineplus.gov/druginfo/meds/a621001.html

Calcium, Magnesium, Potassium, and Sodium Oxybate

pronounced as (kal' see um) (mag nee' zee um)

IMPORTANT WARNING:

Calcium, magnesium, potassium, and sodium oxybate is another name for GHB, a substance that is often illegally sold and abused, especially by young adults in social settings such as nightclubs. Tell your doctor if you drink or has ever drunk large amounts of alcohol, use or have ever used street drugs, or if you have overused prescription medications. Calcium, magnesium, potassium, and sodium oxybate may be harmful when taken by people other than the person for whom it was prescribed. Do not sell or give your calcium, magnesium, potassium, and sodium oxybate to anyone else; selling or sharing it is against the law. Store calcium, magnesium, potassium, and sodium oxybate in a safe place, such as a locked cabinet or box, so that no one else can take it accidentally or on purpose. Keep track of how much liquid is left in your bottle so you will know if any is missing.

Calcium, magnesium, potassium, and sodium oxybate may cause serious side effects, including serious or life-threatening breathing problems. Taking certain medications during your treatment with calcium, magnesium, potassium, and sodium oxybate may increase the risk that you will develop serious or life-threatening breathing problems, sedation, or fainting. Tell your doctor if you take sleeping pills. You doctor will probably tell you not to take calcium, magnesium, potassium, and sodium oxybate while you are taking this medication. Also, tell your doctor if you take antidepressants; benzodiazepines such as alprazolam (Xanax), chlordiazepoxide (Librium), clonazepam (Klonopin), diazepam (Diastat, Valium), estazolam, flurazepam, lorazepam (Ativan), oxazepam, temazepam (Restoril), and triazolam (Halcion); medications for mental illness, nausea, or seizures; muscle relaxants; or narcotic pain medications. You doctor may need to change the doses of your medications and monitor you carefully. Do not drink alcoholic beverages while you are taking calcium, magnesium, potassium, and sodium oxybate.

Calcium, magnesium, potassium, and sodium oxybate is not available at retail pharmacies. Calcium, magnesium, potassium, and sodium oxybate is available only through a restricted distribution program called the Xywav and Xyrem REMS Program. It is a special program to distribute the medication and provide information about the medication. Your medication will be mailed to you from a central pharmacy after you have read the information and talked to a pharmacist. Ask your doctor if you have any questions about how you will receive your medication.

Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with calcium, magnesium, potassium, and sodium oxybate and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also obtain the Medication Guide from the FDA website: https://www.fda.gov/Drugs/DrugSafety/ucm085729.htm.

Keep all appointments with your doctor.

Talk to your doctor about the risks of taking calcium, magnesium, potassium, and sodium oxybate.

Why is this medication prescribed?

Calcium, magnesium, potassium, and sodium oxybate is used to treat attacks of cataplexy (episodes of muscle weakness that begin suddenly and last for a short time) and excessive daytime sleepiness in adults and children 7 years of age and older who have narcolepsy (a sleep disorder that may cause extreme sleepiness, sudden uncontrollable urge to sleep during daily activities, and cataplexy). Calcium, magnesium, potassium, and sodium oxybate is also used to treat adults who have idiopathic hypersomnia (IH; a sleep disorder that may cause excessive daytime sleepiness and uncontrollable urge to sleep during daily activities despite adequate or prolonged nighttime sleep). Calcium, magnesium, potassium, and sodium oxybate is in a class of medications called central nervous system depressants. Calcium, magnesium, potassium, and sodium oxybate works to treat narcolepsy, cataplexy, and idiopathic hypersomnia by reducing activity in the brain.

How should this medicine be used?

Calcium, magnesium, potassium, and sodium oxybate comes as a solution (liquid) to mix with water and take by mouth. When calcium, magnesium, potassium, and sodium oxybate is used to treat cataplexy and excessive daytime sleepiness in patients with cataplexy, it is usually taken twice each night because calcium, magnesium, potassium, and sodium oxybate wears off after a short time, and the effects of one dose will not last for the entire night. When calcium, magnesium, potassium, and sodium oxybate is used to treat idiopathic hypersomnia, it is usually taken once or twice each night. The first dose is taken at bedtime, and a second dose is taken 2 1/2 to 4 hours after the first dose. Calcium, magnesium, potassium, and sodium oxybate must be taken on an empty stomach, so the first dose should be taken at least 2 hours after eating. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand.

Do not take your bedtime doses of calcium, magnesium, potassium, and sodium oxybate until you or your child are in bed and are ready to go to sleep for the night. Calcium, magnesium, potassium, and sodium oxybate begins to work very quickly, within 5 to 15 minutes after taking it. If your doctor has told you to take a second dose, place your second dose of calcium, magnesium, potassium, and sodium oxybate in a safe place near your bed (or in an safe place to give to your child) before sleep. Use an alarm clock to be sure that you will wake up in time to take the second dose. If you or your child wake up before the alarm goes off and it has been at least 2 1/2 hours since you took your first dose, take your second dose, turn off the alarm, and go back to sleep.

Your doctor will probably start you on a low dose of calcium, magnesium, potassium, and sodium oxybate and gradually increase your dose, not more often than once every week.

Calcium, magnesium, potassium, and sodium oxybate may be habit forming. Do not take more of it or take it more often than prescribed by your doctor. If you take too much calcium, magnesium, potassium, and sodium oxybate, you may experience life-threatening symptoms including seizures, slowed or stopped breathing, loss of consciousness, and coma. You may also develop a craving for calcium, magnesium, potassium, and sodium oxybate, feel a need to take larger and larger doses, or want to continue taking calcium, magnesium, potassium, and sodium oxybate even though it causes unpleasant symptoms. If you have taken calcium, magnesium, potassium, and sodium oxybate in amounts larger than prescribed by your doctor, and you suddenly stop taking it, you may experience withdrawal symptoms such as difficulty falling asleep or staying asleep, restlessness, anxiety, abnormal thinking, loss of contact with reality, sleepiness, upset stomach, shaking of a part of your body that you cannot control, sweating, muscle cramps, and fast heartbeat.

Calcium, magnesium, potassium, and sodium oxybate may help to control your symptoms but will not cure your condition. Continue to take calcium, magnesium, potassium, and sodium oxybate even if you feel well. Do not stop taking calcium, magnesium, potassium, and sodium oxybate without talking to your doctor. Your doctor will probably want to decrease your dose gradually. If you suddenly stop taking calcium, magnesium, potassium, and sodium oxybate, you may have more attacks of cataplexy and you may experience anxiety and difficulty falling asleep or staying asleep.

To prepare doses of calcium, magnesium, potassium, and sodium oxybate, follow these steps:

  1. Open the carton that your medicine came in and remove the bottle of medication and the measuring device.
  2. Remove the measuring device from its wrapper.
  3. Open the bottle by pushing down on the cap and turning the cap counterclockwise (to the left) at the same time.
  4. Place the open bottle upright on a table.
  5. Hold the bottle upright with one hand. Use your other hand to place the tip of the measuring device in the center opening on the top of the bottle. Press the tip firmly into the opening.
  6. Hold the bottle and measuring device with one hand. Use your other hand to pull back on the plunger until it is even with the marking that matches the dose your doctor prescribed. Be sure to keep the bottle upright to allow the medication to flow into the measuring device.
  7. Remove the measuring device from the top of the bottle. Place the tip of the measuring device in one of the dosing cups provided with the medication.
  8. Press down on the plunger to empty the medication into the dosing cup.
  9. Add 2 ounces (60 milliliters, 1/4 cup, or about 4 tablespoons) of tap water to the dosing cup. Do not mix the medication with fruit juice, soft drinks, or any other liquid.
  10. Place the cap on dosing cup. Turn cap clockwise (to the right) until it clicks and locks in place.
  11. To prepare a second dose, repeat steps 5 through 10 to prepare a dose of calcium, magnesium, potassium, and sodium oxybate in a second dosing cup.
  12. Rinse the measuring device with water.
  13. Replace the cap on the bottle of calcium, magnesium, potassium, and sodium oxybate and return the bottle and measuring device to a safe place where they are stored away from children and pets. Place prepared dosing cup(s) of medication in a safe place near your bed or in safe place to give your child that is out of the reach of children and pets.
  14. When it is time for you to take the first dose of calcium, magnesium, potassium, and sodium oxybate, press down on the cap and turn it counterclockwise (to the left). Drink all of the liquid while you are sitting on your bed. Put the cap back on the cup, turn it clockwise (to the right) to lock it in place, and lie down right away.
  15. If you are taking a second dose, when you wake up 2 1/2 to 4 hours later to take the second dose, repeat step 14.

Other uses for this medicine

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking calcium, magnesium, potassium, and sodium oxybate,

  • tell your doctor and pharmacist if you are allergic to calcium, magnesium, potassium, and sodium oxybate, any other medications, or any of the ingredients in calcium, magnesium, potassium, and sodium oxybate solution. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
  • some medications should not be taken with calcium, magnesium, potassium and sodium oxybate. Other medications may cause dosing changes or extra monitoring when taken with calcium, magnesium, potassium and sodium oxybate. Make sure you have discussed any medications you are currently taking or plan to take before starting calcium, magnesium, potassium and sodium oxybate with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking calcium, magnesium, potassium and sodium oxybate, please get the advice of your doctor or pharmacist.
  • tell your doctor if you have or ever had succinic semialdehyde dehydrogenase deficiency (an inherited condition in which certain substances build up in the body and cause retardation and developmental delays). Your doctor will probably tell you not to take calcium, magnesium, potassium, and sodium oxybate.
  • tell your doctor if you snore; if you have ever thought about harming or killing yourself or planned or tried to do so; and if you have or have ever had lung disease, difficulty breathing, sleep apnea (a sleep disorder that causes breathing to stop for short periods during sleep), seizures, depression or another mental illness, or liver disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while taking calcium, magnesium, potassium, and sodium oxybate, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking calcium, magnesium, potassium, and sodium oxybate.
  • you should know that you will be very sleepy for at least 6 hours after you take calcium, magnesium, potassium, and sodium oxybate, and you may also be drowsy during the daytime. Do not drive a car, operate machinery, fly an airplane, or perform any other dangerous activities for at least 6 hours after you take your medication. Avoid dangerous activities at all times until you know how calcium, magnesium, potassium, and sodium oxybate affects you.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

If you miss the second dose of calcium, magnesium, potassium, and sodium oxybate, skip the missed dose and continue your regular dosing schedule on the next night. Do not take a double dose to make up for a missed one. Always allow at least 2 1/2 hours between doses of calcium, magnesium, potassium, and sodium oxybate.

What side effects can this medication cause?

Calcium, magnesium, potassium, and sodium oxybate may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • bedwetting
  • headache
  • dizziness
  • shaking of a part of your body that you cannot control
  • feelings of numbness, tingling, pricking, burning, or creeping on the skin
  • difficulty moving when sleeping or upon waking
  • nausea
  • vomiting
  • diarrhea
  • dry mouth
  • irritability
  • weakness
  • muscle spasms
  • sweating

Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them or those listed in the IMPORTANT WARNING section, call your doctor immediately or get emergency medical treatment:

  • sleepwalking
  • abnormal dreams
  • agitation
  • aggression
  • anxiety
  • depression
  • confusion or memory problems
  • changes in weight or appetite
  • feelings of guilt
  • thoughts of harming or killing yourself
  • feeling that others want to harm you
  • hallucinations (seeing things or hearing voices that do not exist)
  • loss of contact with reality
  • breathing problems, snoring, or sleep apnea
  • excessive drowsiness during the day

Calcium, magnesium, potassium, and sodium oxybate may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children and pets. Store it at room temperature and away from excess heat and moisture (not in the bathroom). Pour any remaining medication down the sink if it is more than 24 hours after preparation. Cross out the label on the bottle with a marker and dispose of the empty bottle in the trash. Ask your doctor or call the central pharmacy if you have questions about the proper disposal of your medication if it is outdated or no longer needed.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location — one that is up and away and out of their sight and reach. https://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

  • confusion
  • problems with coordination
  • agitation
  • loss of consciousness
  • coma
  • slow, shallow, or interrupted breathing
  • loss of bladder control
  • loss of bowel control
  • vomiting
  • sweating
  • headache
  • blurred vision
  • muscle jerks or twitches
  • seizure
  • slow heartbeat
  • low body temperature
  • weak muscles

What other information should I know?

Ask your doctor or call the central pharmacy if you have any questions about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Xywav®
Last Revised - 11/15/2021