Belsomra (suvorexant) 15 mg, 100 tablets: profile, composition and research

Reference page for Belsomra (suvorexant) 15 mg, 100 tablets. Active substance: Суворексант / Suvorexant.

Key facts

What suvorexant is

Suvorexant is a sleep medicine of a newer kind that does not belong to the benzodiazepines. It acts on the orexin system, the signalling molecules in the brain that sustain wakefulness.

It is supplied as 15 mg tablets, and a pack contains 100 tablets. The product information states that one tablet holds 15 mg of the active substance.

This is a prescription medicine: it is intended for the treatment of insomnia on a physician's instruction, not for use on one's own.

How suvorexant works

The orexin system

Orexins, also called hypocretins, are neuropeptides produced in the hypothalamus that maintain wakefulness. Their deficiency is associated with narcolepsy.

Receptor blockade

Suvorexant binds reversibly to the orexin receptors of types OX1 and OX2 and prevents the neuropeptides from passing on their signal. As a result the wake-promoting centres receive fewer stimuli.

A dual action

Because both receptor types are blocked, the medicine is classed as a dual orexin receptor antagonist. This distinguishes it from agents acting through the GABA system.

Approved uses

The prescribing information names insomnia that shows itself as difficulty falling asleep and difficulty staying asleep. The medicine is regarded as an option when sleep hygiene and other measures prove insufficient.

The dose is chosen by a physician with age and the medicines taken in mind. The product information notes that older patients are usually given a lower dose, though the decision remains with a specialist.

Treatment should not be started or stopped on one's own: discontinuation is planned together with a physician so that symptoms do not return.

What the research shows

In a randomised study published in 2012, suvorexant was compared with placebo in patients with primary insomnia, and the time to fall asleep and the total duration of sleep were assessed.

Two three-month studies, together with a one-year follow-up study, examined how the effect is maintained and what follows abrupt discontinuation. The data point to sleep being sustained through treatment.

Some questions remain open: many years of use and comparisons with other classes of sleep medicines have been studied to a limited extent, so conclusions are drawn cautiously.

Published research

Primary sources, verified against PubMed:

• Orexin receptor antagonism for treatment of insomnia: a randomized clinical trial of suvorexant., PubMed 23197752 (Neurology, 2012).
• Safety and efficacy of suvorexant during 1-year treatment of insomnia with subsequent abrupt treatment discontinuation: a phase 3 randomised, double-blind, placebo-controlled trial., PubMed 24680372 (Lancet Neurol, 2014).
• Suvorexant in Patients With Insomnia: Results From Two 3-Month Randomized Controlled Clinical Trials., PubMed 25526970 (Biol Psychiatry, 2016).
• The Discovery of Suvorexant, the First Orexin Receptor Drug for Insomnia., PubMed 27860547 (Annu Rev Pharmacol Toxicol, 2017).

Listed for reference. Publication of a study is not a claim about this particular product.

Precautions

• This is a prescription medicine. Prescribing, dosing and discontinuation belong to a physician.
• Daytime drowsiness and reduced alertness are possible, so driving and operating machinery call for caution.
• Complex sleep behaviours have been described, including walking and eating while not fully awake. Such episodes should be reported to a doctor.
• Sleep paralysis and hallucinations on falling asleep are possible, as is a worsening of mood.
• It must not be combined with alcohol, and other sleep medicines and agents affecting liver enzymes only after agreement with a physician.
• In pregnancy and breastfeeding the decision belongs to a specialist.

Frequently asked