Xyrem (sodium oxybate) oral solution is indicated for the treatment of excessive daytime sleepiness and cataplexy in patients with narcolepsy.In Xyrem clinical trials, approximately 80% of patients maintained concomitant stimulant use (see BLACK BOX WARNINGS).

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Excessive daytime somnolence --

Cataplexy -- A condition characterized by transient weakness or paralysis of somatic musculature triggered by an emotional stimulus or physical exertion. Cataplexy is frequently associated with NARCOLEPSY. During a cataplectic attack, there is a marked reduction in muscle tone similar to the normal physiologic hypotonia that accompanies rapid eye movement sleep (SLEEP, REM). (From Adams et al., Principles of Neurology, 6th ed, p396)

Narcolepsy -- A condition characterized by recurrent episodes of daytime somnolence and lapses in consciousness (microsomnias) that may be associated with automatic behaviors and AMNESIA. CATAPLEXY; SLEEP PARALYSIS, and hypnagogic HALLUCINATIONS frequently accompany narcolepsy. The pathophysiology of this disorder includes sleep-onset rapid eye movement (REM) sleep, which normally follows stage III or IV sleep. (From Neurology 1998 Feb;50(2 Suppl 1):S2-S7)

Sodium oxybate is contraindicated in patients being treated with sedative hypnotic agents.Sodium oxybate is contraindicated in patients with succinic semialdehyde dehydrogenase deficiency.

This rare disorder is an inborn error of metabolism variably characterized by mental retardation, hypotonia, and ataxia.

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SUCCINIC SEMIALDEHYDE DEHYDROGENASE DEFICIENCY --

Rare Diseases -- A large group of diseases which are characterized by a low prevalence in the population. They frequently are associated with problems in diagnosis and treatment.

Muscle hypotonia -- A diminution of the skeletal muscle tone marked by a diminished resistance to passive stretching.

Ataxia -- Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or PERIPHERAL NERVE DISEASES. Motor ataxia may be associated with CEREBELLAR DISEASES; CEREBRAL CORTEX diseases; THALAMIC DISEASES; BASAL GANGLIA DISEASES; injury to the RED NUCLEUS; and other conditions.

SEE BOXED WARNINGDue to the rapid onset of its CNS depressant effects, sodium oxybate should only be ingested at bedtime, and while in bed.

For at least 6 hours after ingesting sodium oxybate, patients must not engage in hazardous occupations or activities requiring complete mental alertness or motor coordination, such as operating machinery, driving a motor vehicle, or flying an airplane.

When patients first start taking Xyrem or any other sleep medicine, until they know whether the medicine will still have some carryover effect on them the next day, they should use extreme care while performing any task that could be dangerous or requires full mental alertness.The combined use of alcohol (ethanol) with sodium oxybate may result in potentiation of the central nervous system-depressant effects of sodium oxybate and alcohol.

Therefore, patients should be warned strongly against the use of any alcoholic beverages in conjunction with sodium oxybate.

Sodium oxybate should not be used in combination with sedative hypnotics or other CNS depressants.