The importance of proper XYREM dosing and titration.

Across all pivotal trials, the effective dosage range for XYREM was 6 g to 9 g per night.1

  • XYREM is an oral solution, taken at night in 2 equal, divided doses.1
  • The recommended starting dosage is 4.5 g per night (as two 2.25 g doses).1
  • The FDA-approved maximum dosage of XYREM is 9 g per night (as two 4.5 g doses).1

Follow these steps to start and titrate your patients with XYREM.

  • XYREM is taken in 2 equal doses at night due to its short half-life.1
  • Start dosing at 4.5 g per night administered orally in 2 equal, divided doses: 2.25 g at bedtime and 2.25 g taken 2.5 to 4 hours later.1
  • Titrate to effect in increments of 1.5 g per night at weekly intervals (an additional 0.75 g at bedtime and another 0.75 g taken 2.5 to 4 hours later).1
  • Dosages higher than 9 g per night have not been studied and should not ordinarily be administered.1

It is recommended that XYREM be titrated at weekly intervals, by adding 1.5 g per night, from 4.5 g to the effective dosage range of 6 g to 9 g per night.1

Once an effective dosage is reached, patient follow-up every 3 months is recommended.1

Starting and Titrating XYREM1

Starting and Titrating XYREM

Patients should be assessed frequently for symptom response and adverse reactions.

Patients should be continually assessed for CNS depression-related events.

Important Safety Information

Dose-Response Information: In clinical trials in narcolepsy, a dose-response relationship was observed for nausea, vomiting, paresthesia, disorientation, irritability, disturbance in attention, feeling drunk, sleepwalking, and enuresis. The incidence of all these reactions was notably higher at 9 g per night. In controlled trials in narcolepsy, discontinuations of treatment due to adverse reactions were greater at higher doses of XYREM.


Dose Modification in Patients with Hepatic Impairment: The recommended starting dose in patients with hepatic impairment is 2.25 g per night administered orally in two equal, divided doses: approximately 1.13 g at bedtime and approximately 1.13 g taken 2.5 to 4 hours later.


Dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

How to convert XYREM dosages from g to mL.

  • XYREM is packaged in 6-ounce bottles (180 mL) with a concentration of 500 mg/mL (0.5 g/mL).1
  • XYREM is dispensed by the central Certified Pharmacy in a maximum 30-day supply for the initial fill, and a maximum 90-day supply for each refill.2 Insurance plans, electronic medical record systems, or ePrescribe platforms may require conversion of XYREM in milliliters or bottles.
  • The recommended dosage for XYREM per the full Prescribing Information equates to the total monthly quantities below.1

Dosing Conversion Calculator (g to mL)

Dosing Conversion Calculator (g to mL)

How to enter titration information with EMR systems or when e-prescribing.

  • There may be a restriction to the number of characters allowable when utilizing EMR systems or when e-prescribing. Here is an example of a simple way to enter the XYREM titration schedule in an electronic database.

Sample Electronic Titration Entry

Sample Electronic Titration Entry