Section 10 · Monograph

Suvorexant

Reviewed Nov 2026FDA label

BelsomraOrexin receptor antagonist

Indications

Treatment of insomnia, characterized by difficulties with sleep onset and/or sleep maintenance, in adultsFDA-labeled
Core FDA indication is general adult insomnia — treatment of insomnia characterized by difficulties with sleep onset and/or sleep maintenance — the same mechanistic class (dual orexin receptor antagonist / DORA) as lemborexant; available as 5/10/15/20 mg tablets with a recommended starting dose of 10 mg (max 20 mg/night) taken within 30 minutes of bedtime with at least 7 hours before planned awakening; Schedule IV controlled substance.FDA-labeled

Management of sleep disturbance and nocturnal agitation in patients with dementia, including Alzheimer's diseaseOff-label

Orexin receptor antagonist
Orexin neuropeptides (orexin A and B) are wake-promoting neurotransmitters from the lateral hypothalamus that bind OX1R and OX2R to stabilize wakefulness
Suvorexant binds competitively to both OX1R and OX2R as a dual orexin receptor antagonist, blocking the wake-promoting neuropeptides
Suppresses the arousal/wakefulness drive rather than directly sedating via GABAergic pathways, distinguishing it from benzodiazepines and Z-drugs

Recommended starting dose: 10 mg orally once nightly, within 30 minutes of bedtime, with at least 7 hours remaining before planned awakening
May increase dose based on clinical response and tolerability, but do not exceed 20 mg once daily
Use the lowest effective dose for the individual patient
Concomitant moderate CYP3A inhibitors (diltiazem, fluconazole, verapamil): limit dose to 5 mg once nightly, not to exceed 10 mg
Concomitant strong CYP3A inhibitors (ketoconazole, itraconazole, ritonavir, clarithromycin): coadministration not recommended
Schedule IV controlled substance — prescribe the minimum quantity consistent with good patient care

Mild-to-moderate hepatic impairment: no dosage adjustment necessary; not recommended in severe hepatic impairment

Strong CYP3A inhibitors: coadministration not recommended due to substantially increased suvorexant exposure
Moderate CYP3A inhibitors: dose should be limited to 5 mg once nightly (max 10 mg)
Strong CYP3A inducers (rifampin, carbamazepine, phenytoin, St. John's Wort): substantially decrease exposure and may reduce efficacy; not recommended
CNS depressants (benzodiazepines, opioids, TCAs, other sedative-hypnotics): additive CNS depressant effects
Alcohol: additive impairment of psychomotor performance and next-day alertness
Digoxin: weak P-glycoprotein inhibition may modestly increase digoxin plasma concentrations; monitor with concomitant use

Somnolence/next-day drowsiness, dose-related
Headache
Dizziness
Abnormal dreams
Dry mouth
CNS depressant effects and next-day psychomotor/driving impairment, particularly at 20 mg dose
Complex sleep behaviors, including sleep-walking and sleep-driving with amnesia for the event
Mild cataplexy-like symptoms (transient leg weakness), sleep paralysis, hypnagogic/hypnopompic hallucinations
Suicidal ideation and worsening of pre-existing depression reported in a small number of patients
Potential for abuse and physical dependence given Schedule IV classification

Reassess for underlying causes of insomnia if symptoms fail to improve within 7-10 days
Assess for daytime somnolence, sedation, and impaired alertness, especially in elderly or dementia patients at higher fall risk
Monitor for signs of complex sleep-related behaviors
Screen for worsening depression or emergence of suicidal ideation
Evaluate for symptoms of cataplexy-like leg weakness, sleep paralysis, or hallucinations
Monitor for signs of misuse, abuse, or dependence given controlled-substance status
In dementia patients, monitor cognition and functional status for any paradoxical worsening or increased confusion

Available data are insufficient to establish a drug-associated risk of major birth defects or miscarriage
Animal reproduction studies showed decreased fetal/pup weight and other developmental effects only at maternally toxic doses
Suvorexant and its major metabolite are present in low concentrations in human breast milk, with an estimated relative infant dose of less than 1% of the maternal weight-adjusted dose
No adverse effects on the breastfed infant have been reported