SODIUM OXYBATE (GHB)
| SODIUM OXYBATE (GHB) (sod'i-um ox'y-bate) Xyrem Classifications: central nervous system (cns) depressant; Therapeutic: cns depressant Pregnancy Category: B Controlled Substance: Schedule III |
Availability
500 mg/mL solution
Action
CNS depressant; the precise mechanism by which sodium oxybate produces anticataplexy in narcolepsy is unknown. Sodium oxybate is GHB, a known drug of abuse.
Therapeutic Effect
Produces anticataplectic effects in narcolepsy and decreases the number of cataplexy events in individuals with narcolepsy. Also has sedative and amnestic properties.
Uses
Treatment of cataplexy in patients with narcolepsy.
Contraindications
Alcohol or sedative-hypnotics or other CNS depressants; patients being treated with sedative-hypnotic agents; psychosis; coma; eclampsia; patients with succinic semialdehyde dehydrogenase deficiency; compromised respiratory drive, severe depression, or suicidal tendencies; lactation; children <16 y.
Cautious Use
Hepatic dysfunction; compromised respiratory function; sleep disorders; history of seizures; heart failure, hypertension, impaired renal function; previous history of depressive illness or suicide attempt; elderly; sleep-walking; pregnancy (category B).
Route & Dosage
| Cataplexy Adult: PO Start with 2.25 g given at bedtime while in bed and repeated 2.5–4 h later. Dose may be increased by 1.5 g/d every 2 wk to a max of 9 g/d in 2 divided doses. Hepatic Impairment Reduce dose by 50% in patients with hepatic impairment. |
Administration
Oral- Give at bedtime at least 2–3 h after the evening meal.
- Dilute each dose with 2 oz (60 mL) of water in the dosing cups provided.
- Instruct patient to remain in bed after taking sodium oxybate.
- Discard any diluted dose that has not been used within 24 h.
- Store at 15°–30° C (59°–86° F).
Adverse Effects (≥1%)
Body as a Whole: Pain, infection, flu-like syndrome, asthenia, allergic reactions, chills. CNS: Confusion, depression, sleepwalking, headache, dizziness, somnolence, nervousness, abnormal dreams, insomnia, agitation, ataxia, convulsion, stupor, tremor. CV: Hypertension. GI: Nausea, diarrhea, vomiting, dyspepsia, abdominal pain, anorexia, constipation. Metabolic: Increased alkaline phosphatase, edema, hypercholesteremia, hypocalcemia, weight gain. Respiratory: Pharyngitis, rhinitis, sinusitis Skin: Increased sweating, acne, alopecia, rash. Special Senses: Amblyopia, tinnitus. Urogenital: Urinary incontinence, dysmenorrhea, albuminuria, cystitis, hematuria, metrorrhagia, urinary frequency.Interactions
Drug: Alcohol, sedative-hypnotics, other cns depressants may increase CNS depressant effects. Food: High-fat meal will significantly reduce absorption.Pharmacokinetics
Absorption: Incompletely absorbed, 25% reaches systemic circulation. Peak: 0.05–1.25 h. Metabolism: Oxidized in the Krebs' cycle to carbon dioxide and water. Elimination: Primarily eliminated as carbon dioxide in respiration. Half-Life: 0.5–1 h.Nursing Implications
Assessment & Drug Effects
- Monitor for and report immediately any of the following: seizure, respiratory depression, or decreased level of consciousness.
- Monitor closely patients with hepatic insufficiency for adverse events.
- Monitor for and report excessive weight gain and development of edema.
- Lab tests: Perform baseline LFTs; monitor periodically serum electrolytes and lipid profile.
Patient & Family Education
- Do not take sodium oxybate at any time other than at night, immediately before bedtime.
- Be consistent with timing of the evening meal and take this drug at least 2–3 h after eating.
- Prepare both doses prior to bedtime. After ingesting each dose remain in bed.
- Do not consume alcohol or use other sedative hypnotic drugs with sodium oxybate.
- Do not drive or engage in potentially hazardous activities until reaction to drug is known.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug