Skip to main content

Sodium oxybate


Take sodium oxybate two times each night.

Take your first dose as you go to bed and the second dose 2½-4 hours later.

Sodium oxybate will make you feel sleepy. If you still feel sleepy the next day, do not drive and do not use tools or machines.

Continue reading below

About sodium oxybate

Type of medicine

Central nervous system depressant

Used for

Narcolepsy with cataplexy

Also called


Available as

Oral liquid medicine

Narcolepsy is a problem which affects your sleep. Disturbed night-time sleep makes you feel very tired and drowsy during the daytime, and you can also have times where you fall asleep during the day without any warning. Many people with narcolepsy also have cataplexy. Cataplexy is a condition in which you suddenly lose control over some of your muscles.

Sodium oxybate is used to treat narcolepsy when cataplexy is also a problem. It helps with excessive daytime sleepiness as well as helping the symptoms of cataplexy. It is sometimes used in combination with other medicines for narcolepsy.

Before taking sodium oxybate

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking sodium oxybate it is important that your doctor or pharmacist knows:

  • If you are pregnant, trying for a baby or breastfeeding.

  • If you have epilepsy.

  • If you have any problems with your heart or your breathing, or if you have high blood pressure.

  • If you have problems with your liver or kidneys.

  • If you are on a 'low sodium' diet for medical reasons.

  • If you have ever had a depressive illness.

  • If you have porphyria, a rare inherited blood disorder.

  • If you have ever had a drug addiction problem.

  • If you are taking any other medicines. This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines.

  • If you have ever had an allergic reaction to a medicine.

Continue reading below

How to take sodium oxybate

  • Before you start this treatment, read the manufacturer's printed information leaflet from inside your pack. The leaflet will give you more information about sodium oxybate and a full list of side-effects which you may experience from taking it.

  • Take sodium oxybate exactly as your doctor tells you to. When starting this treatment your doctor will give you a small dose and then gradually increase it. This is to make sure you have the dose that helps your condition and avoids any unwanted symptoms.

  • It is taken in two doses - the first dose taken as you go to bed, and the second dose 2½-4 hours later. You should prepare both doses before you retire to bed, and you may need to set an alarm to make sure you wake up to take the second dose.

  • Only use the special child-resistant dosing cups provided with Xyrem® for storing your diluted doses.

  • Sit upright whilst taking your doses. Take your second dose whilst still in bed and lie down again straightaway.

  • Food interferes with how much of this medicine is absorbed by your body, so it is important that you take sodium oxybate well after eating any food. Most doctors will recommend that it is taken at a set time each evening, at least 2-3 hours after your evening meal.

  • Mix each of your doses with water (see below).

  • If you forget to take the first dose, take it as soon as you remember and then take the second dose 2½-4 hours later. If you forget to take the second dose, do not take it when you remember but instead skip the dose completely and do not take any more until the following evening. Do not take two doses together to make up for a forgotten dose.

Instructions for using Xyrem® Oral Solution

  1. Remove the bottle cap and the foil seal. Push the plastic adaptor into the top of the open bottle.

  2. Insert the syringe into the adapter.

  3. Keeping the bottle upright, gently pull out the plunger of the syringe so that the solution fills the syringe to the mark which corresponds to your dose.

  4. Remove the syringe from the bottle, and empty the liquid from the syringe into the dosing cup.

  5. Repeat steps 2-4 to prepare your second dose.

  6. Add 60 ml of water (about four tablespoons) to both dosing cups, and then close both of the cups with the locking caps provided.

  7. Replace the cap on the bottle of Xyrem® Oral Solution, leaving the adapter in place. Wash the syringe with water.

Getting the most from your treatment

  • Keep your regular appointments with your doctor. This is so your progress can be monitored.

  • Treatment with sodium oxybate is usually long-term. Continue to take the medicine unless you are advised otherwise. Stopping suddenly can cause problems and your doctor may want you to reduce your dose gradually if this is necessary.

  • Sodium oxybate will make you sleepy, so do not drive within six hours of taking a dose. You may also continue to feel sleepy during the following day, so do not drive and do not use tools or machines if this happens, as you may put yourself and others at risk.

  • You should not drink alcohol while you are on sodium oxybate.

  • If you buy any medicines, check with a pharmacist that they are suitable for you to take with sodium oxybate. Some strong painkillers should not be taken with this medicine.

  • If you are having an operation or dental treatment, tell the person carrying out the treatment that you are taking this medicine.

  • Sodium oxybate is known to cause dependence, particularly where more than the recommended doses are taken. If you are concerned about this, you should discuss it with your doctor.

Continue reading below

Can sodium oxybate cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. These usually improve as your body adjusts to the new medicine, but speak with your doctor or pharmacist if any of the following side-effects continue or become troublesome.

Very common sodium oxybate side-effects - these affect more than 1 in 10 people who take this medicine

What can I do if I experience this?

Feeling dizzy

Move around more slowly. Do not drive and do not use tools or machines until you feel better

Feeling sick (nausea)

Stick to simple meals, avoid rich or spicy food


Drink plenty of water and ask a pharmacist to recommend a suitable painkiller. If the headaches continue, let your doctor know

If you experience other symptoms which you think may be due to this medicine, speak with your doctor or pharmacist.

How to store sodium oxybate

  • Keep all medicines out of the reach and sight of children.

  • Store in a cool, dry place, away from direct heat and light.

  • Once a bottle has been opened it will keep for 90 days; after this time, make sure you have a fresh supply.

  • Diluted liquid should only be kept for 24 hours.

Important information about all medicines

Important information about all medicines

Never take more than the prescribed dose. If you suspect that you or someone else might have taken an overdose of this medicine, go to the accident and emergency department of your local hospital at once. Take the container with you, even if it is empty.

This medicine is for you. Never give it to other people even if their condition appears to be the same as yours.

Do not keep out-of-date or unwanted medicines. Take them to your local pharmacy which will dispose of them for you.

If you have any questions about this medicine ask your pharmacist.

Report side effects to a medicine or vaccine

If you experience side effects, you can report them online through the Yellow Card website.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

symptom checker

Feeling unwell?

Assess your symptoms online for free