The US Food and Drug Administration (FDA) has approved Belsomra (suvorexant) for adults with insomnia who have difficulty falling asleep and/or staying asleep. Belsomra (pronounced bell-SOM-rah) is a highly selective antagonist for orexin receptors, according to manufacturer Merck (Merck is known as MSD outside the United States and Canada). Orexin is a neurotransmitter found in a specific part of the brain that can help keep a person awake.

The mechanism by which Belsomra exerts its therapeutic effect is presumed to be through antagonism of orexin receptors. In the clinical trials to support efficacy, Belsomra was superior to placebo for sleep latency and sleep maintenance as assessed both objectively by polysomnography and subjectively by patient-estimated sleep latency. The recommended dose is 10 mg, taken no more than once per night and within 30 minutes of going to bed, with at least 7 hours remaining before the planned time of awakening. The total dose should not exceed 20 mg once daily.

“Today’s approval of Belsomra allows for the introduction of a new treatment option for patients suffering from insomnia,” says Dr David Michelson, vice president, Neurosciences, Merck Research Laboratories, in a release. “Belsomra is the result of more than a decade of Merck research in neuroscience and provides tangible evidence of our long-standing commitment to innovation.”

The FDA has recommended Belsomra be classified by the Drug Enforcement Administration (DEA) as a scheduled product. Earlier this year, the DEA proposed a Schedule IV drug classification under the Controlled Substances Act. The DEA has not yet issued a final decision on the scheduling for Belsomra and therefore the product cannot become available before that decision.


Belsomra (suvorexant) is indicated for the treatment of insomnia characterized by difficulties with sleep onset and/or sleep maintenance.

Select Safety Information

Belsomra is contraindicated in patients with narcolepsy.

Belsomra can impair daytime wakefulness. Central nervous system (CNS) depressant effects can last for up to several days after discontinuation.

Belsomra can impair driving skills and may increase the risk of falling asleep while driving.

Coadministration with other CNS depressants (eg, benzodiazepines, opioids, tricyclic antidepressants, alcohol) increases the risk of CNS depression. Patients should be advised not to consume alcohol in combination with Belsomra because of additive effects. Dosage adjustments of Belsomra and of concomitant CNS depressants may be necessary when administered together because of potentially additive effects. The use of Belsomra with other drugs to treat insomnia is not recommended.

The risk of next-day impairment, including impaired driving, is increased if Belsomra is taken with less than a full night of sleep remaining, if a higher than the recommended dose is taken, if coadministered with other CNS depressants, or if coadministered with other drugs that increase blood levels of Belsomra. Patients should be cautioned against driving and other activities requiring complete mental alertness if taken in these circumstances.

Caution patients taking 20 mg against next day driving and other activities requiring full mental alertness.

Reevaluate patients for comorbid conditions if insomnia persists after 7 to 10 days of treatments.

A variety of cognitive and behavioral changes (eg, amnesia, anxiety, hallucinations, and other neuro-psychiatric symptoms) have been reported to occur in association with the use of hypnotics such as Belsomra. “Sleep driving” (ie, driving while not fully awake) and other complex behaviors (eg, preparing and eating food, making phone calls, or having sex), with amnesia for the event, have been reported with the use of hypnotics. These events can occur in hypnotic-naïve as well as in hypnotic-experienced persons.

The use of alcohol and other CNS depressants may increase the risk of such behaviors.

Discontinuation of Belsomra should be strongly considered for patients who report any complex sleep behavior.

In clinical studies, a dose-dependent increase in suicidal ideation was observed in patients taking Belsomra, as assessed by questionnaire. Immediately evaluate patients with suicidal ideation or any new onset behavioral changes. Worsening depression or suicidal thinking, thoughts, and actions have been reported with the use of sedative-hypnotics. Suicidal tendencies may be present in such patients and protective measures may be required. Intentional overdose is more common in this group of patients; therefore, the lowest number of tablets that is feasible should be prescribed for the patient at any one time.

The effect of Belsomra on respiratory function should be considered.

The risk of sleep paralysis, hypnagogic/hypnopompic hallucinations, and cataplexy-like symptoms increases with increasing doses of Belsomra.

Belsomra is not recommended for patients with severe hepatic impairment or those taking a strong CYP3A inhibitor.

In clinical studies, the most common adverse reaction (reported in 5% or more of patients treated with 15 or 20 mg of Belsomra and at least twice the placebo rate) was somnolence (Belsomra 6.7%; placebo 3.0%).

The recommended dose of Belsomra is 5 mg in patients receiving moderate CYP3A inhibitors.

Digoxin levels should be monitored closely as slight increases were seen with coadministration of Belsomra.

Belsomra Availability

Belsomra is expected to be available in late 2014 or early 2015. Healthcare professionals and patients in the United States interested in receiving an e-mail when it becomes available can register by visiting