sodium oxybate: clinical use

Prescribing considerations

• Initiation and ongoing supervision should remain with a clinician experienced in narcolepsy.
• Assess respiratory disease, sleep apnoea risk, psychiatric history, suicidality and susceptibility to substance misuse before treatment.
• Consider the high sodium burden in hypertension, heart failure, renal impairment or patients advised to restrict salt.
• Hepatic impairment substantially increases exposure; consult the product-specific SmPC before prescribing.
• Epilepsy and porphyria require particular caution; use in epilepsy is not recommended.

Contraindications and cautions

• Hypersensitivity to sodium oxybate or an excipient
• Succinic semialdehyde dehydrogenase deficiency
• Major depression
• Concurrent opioid treatment
• Concurrent barbiturate treatment

Monitoring

• Cataplexy, daytime sleepiness and night-time sleep quality
• Respiratory depression, snoring, choking and sleep-apnoea symptoms
• Depression, suicidality, psychosis, confusion and behavioural change
• Sleepwalking, falls and urinary or faecal incontinence
• Misuse, dependence, diversion or unexplained loss
• Weight and growth in paediatric patients; motor and cognitive function in older adults
• Blood pressure, fluid status and dietary sodium where clinically relevant

Clinical pharmacology

Sodium oxybate is rapidly absorbed, with food reducing and delaying absorption. Pharmacokinetics are nonlinear. It is metabolised mainly through GHB dehydrogenase and the Krebs cycle to carbon dioxide and water; renal elimination of unchanged sodium oxybate is minor, and clinically important CYP inhibition is not expected.

Formulation and product differences

• The selected product is a sugar-free, clear, colourless oral solution with a high sodium content.
• It contains purified water, malic acid and sodium hydroxide and is supplied with a measuring syringe, bottle adaptor and two child-resistant dosing cups.
• Prepared diluted solution must be stored and discarded according to product instructions; the original bottle should be protected from light.

Oral solution

Route: Oral

Strengths: 500 mg/mL