Suvorexant (Belsomra)

Primer

Suvorexant (Trade name: Belsomra) is a dual orexin receptor antagonist (DORA) used in the treatment of insomnia disorder.

Pharmacokinetics

Pharmacokinetics of Suvorexant

Absorption
Distribution
Metabolism
Elimination
Half-life

Suvorexant: Cytochrome P450 Metabolism

Substrate of (Metabolized by)
Induces
Inhibits

Pharmacodynamics

Mechanism of Action

Toxicity

Indications

Dosing

Dosing for Suvorexant

Starting
Titration
Maximum
Taper

Formulations

  • Suvorexant comes in

Monitoring

Contraindications

Absolute

Relative

Drug-Drug Interactions

Side Effects

Adverse Events

  • There is an increased risk of somnolence, daytime sleepiness, impaired reaction time and impaired driving skills.
  • Concerns have also been raised regarding unconscious nighttime activity, sleep paralysis, hypnagogic hallucinations, mild cataplexy, and suicidal ideation with suvorexant use.[1]
    • These adverse effects have a dose-dependent relationship; patients treated with up to four times the maximum recommended dose experienced somnolence twice as frequently as those treated with the recommended dose (10 mg and 20 mg). In fact, the Food and Drug Administration (FDA) initially rejected high doses of suvorexant 30 mg and 40 mg proposed by the manufacturer (Merck), because it posed a dangerous risk of next-day drowsiness that could lead to driving accidents. The FDA eventually approved lower doses of the drug (5 mg, 10 mg, and 20 mg) to mitigate this side effect.

Clinical Pearls

Special Populations

Geriatric

Pediatric

Obstetric and Fetal

Medically Ill

Resources

For Patients
Research

References

1) Rhyne, D. N., & Anderson, S. L. (2015). Suvorexant in insomnia: efficacy, safety and place in therapy. Therapeutic Advances in Drug Safety, 6(5), 189-195.