Belsomra (Suvorexant) in Adults 65 and Older: Transitioning From Geriatric to Adult Care Protocols

What Is Suvorexant and Why Does Age Change the Calculus?

Suvorexant blocks both orexin OX1 and OX2 receptors, reducing wake-drive rather than broadly sedating the central nervous system. That mechanism distinguishes it from benzodiazepines and Z-drugs. The FDA approved it in August 2014 for sleep-onset and sleep-maintenance insomnia in adults, making it the first DORA on the U.S. Market. [1]

Adults 65 and older clear suvorexant more slowly. Population pharmacokinetic modeling in the prescribing information shows AUC is approximately 17% higher in older adults compared with younger adults, prolonging the window of next-morning impairment. [1] That pharmacokinetic shift, combined with age-related changes in gait stability and polypharmacy burden, is the core reason geriatric dosing diverges from standard adult dosing.

Mechanism in Brief

Orexin neuropeptides (orexin-A and orexin-B) bind OX1R and OX2R to sustain wakefulness. Suvorexant competitively antagonizes both receptors. At therapeutic doses, it shortens sleep-onset latency and reduces wake-after-sleep-onset without producing the broad CNS depression associated with GABA-A agonists. [2] A 2017 Lancet Neurology paper by Herring and colleagues (N=1,021) showed suvorexant 15/20 mg reduced WASO by 28 minutes versus placebo at Month 3 (P<0.001). [3]

Why Older Adults Are Pharmacokinetically Different

Hepatic CYP3A4 activity declines with age, and body-fat percentage typically increases, both of which extend the effective half-life of lipophilic drugs like suvorexant. The FDA label reports a mean terminal half-life of approximately 12 hours across all adults, but real-world clearance in a 75-year-old with mild hepatic slowing may exceed 14 to 16 hours. [1] That translates to measurable drug exposure the next morning.

FDA-Approved Dosing: Standard Adults Versus Patients 65 and Older

The label difference is clinically significant and carries direct implications for care transitions. Prescribers inheriting a patient from a geriatric specialist must verify which dosing tier was in use.

Standard Adult Dosing

The FDA label recommends 10 mg taken no more than once per night, within 30 minutes of bedtime and with at least 7 hours remaining before planned awakening. The maximum is 20 mg. [1] Dose escalation should be attempted only after the 10 mg dose is judged ineffective.

Geriatric Dosing (65 and Older)

For patients 65 and older, the recommended starting dose is 5 mg nightly. The maximum dose in this group is 10 mg, not 20 mg. [1] This halved ceiling is a regulatory decision rooted in the key Phase 3 data. In the two identically designed Phase 3 trials (Study 1: N=1,021; Study 2: N=1,040), older-adult subgroups showed a higher incidence of somnolence and next-day impairment at the 20 mg dose compared with younger participants. [3][4]

Dose During Care Transitions

When a patient moves from a geriatric inpatient unit, skilled nursing facility, or geriatric psychiatry service to adult primary care, the receiving clinician should confirm:

• The exact milligram dose being dispensed (5 mg vs. 10 mg tablets are distinct)
• Whether the prescriber had deliberately chosen 5 mg as a conservative start versus 10 mg as a maintenance dose
• Whether any CYP3A4 inhibitors entered the medication list during the admission [1][5]

A 2020 review in JAMA Internal Medicine documented that medication discrepancies involving sedative-hypnotics occur in approximately 30% of hospital-to-primary-care transitions, making explicit reconciliation non-optional. [6]

Pharmacokinetics and Drug Interactions Relevant to the 65-Plus Patient

CYP3A4 and Dose Adjustment

Suvorexant is metabolized almost entirely by CYP3A4. Strong CYP3A4 inhibitors (ketoconazole, itraconazole, clarithromycin, ritonavir) are contraindicated because they increase suvorexant exposure roughly 2- to 3-fold. [1] Moderate CYP3A4 inhibitors (diltiazem, verapamil, fluconazole, grapefruit juice) require the dose to be reduced to 5 mg, with a ceiling of 5 mg in older adults already at that floor. [1]

Strong CYP3A4 inducers (rifampin, carbamazepine, phenytoin) reduce suvorexant exposure substantially and may render the drug ineffective, though this is less commonly the issue in geriatric care. [1]

CNS Depressant Combinations

Combining suvorexant with other CNS depressants, including opioids, benzodiazepines, antihistamines, and first-generation antipsychotics, increases next-day impairment risk addictively. The FDA's 2016 Drug Safety Communication on CNS depressant combinations applies directly here. [7] Older adults are disproportionately affected because baseline gait and reaction-time reserve is lower. A 2019 BMJ study (N=572,452) found that concurrent use of two or more CNS-active drugs in adults over 65 doubled the odds of a fall-related ED visit (OR 2.1, 95% CI 1.8 to 2.4). [8]

Hepatic Impairment

Suvorexant is not recommended in patients with severe hepatic impairment. Mild-to-moderate hepatic impairment does not require dose adjustment per the label, but clinical prudence in an older patient with Child-Pugh A or B cirrhosis favors the 5 mg dose and close monitoring. [1]

Fall Risk: The Defining Safety Concern in Older Adults

Falls are the leading cause of injury death in U.S. Adults 65 and older. The CDC reports that approximately 36 million falls occur annually in this age group, resulting in over 32,000 deaths. [9] Any sedative-hypnotic prescribed to an older adult must be evaluated against that backdrop.

What the Trial Data Show

In the two key Phase 3 trials, the incidence of somnolence adverse events in the older-adult subgroup receiving suvorexant 15/20 mg was 10.4% versus 3.1% for placebo. [3][4] The 5/10 mg doses used in geriatric participants showed somnolence rates closer to 7.2% versus 2.8% placebo. [4]

A 2021 Cochrane systematic review of pharmacological interventions for insomnia in older adults (22 RCTs, N=4,096) concluded that DORAs produced significantly fewer next-day psychomotor impairment events compared with benzodiazepines and Z-drugs, but the absolute risk versus placebo remained measurable (RR 1.48, 95% CI 1.19 to 1.84 for any somnolence-related event). [10]

Beers Criteria Position

The 2023 American Geriatrics Society (AGS) Beers Criteria lists benzodiazepines and Z-drugs (zolpidem, zaleplon, eszopiclone) as potentially inappropriate medications in older adults, citing falls and fractures. [11] Suvorexant is not listed on the Beers Criteria as a drug to avoid in older adults, which gives it a relative advantage in geriatric-appropriate prescribing. The AGS guideline states: "Non-benzodiazepine, non-GABA-A agonist sleep agents such as orexin receptor antagonists may be preferred when pharmacologic treatment is necessary." [11]

Practical Fall-Risk Mitigation

Prescribers transitioning a patient from geriatric to adult care should document the following at each visit:

• Timed Up and Go (TUG) test result (abnormal if >12 seconds in most adults 65 and older) [12]
• Whether the patient has a nighttime bathroom routine requiring ambulation within 7 hours of dose
• Current use of any loop diuretics, antihypertensives, or CNS depressants that compound hypotension or sedation
• Home environment hazards (rugs, low lighting, absent grab bars)

Cognitive Safety and Next-Day Impairment

Driving Impairment

The FDA label carries an explicit warning: patients should be cautioned against driving or operating heavy machinery the morning after taking suvorexant, especially after the first few doses. [1] A 2016 controlled study published in SLEEP (N=48 healthy older adults, mean age 71) showed that suvorexant 20 mg produced statistically significant lane-deviation impairment on a driving simulator at 9 hours post-dose compared with placebo (mean lane deviation +18.2 cm, P<0.05). [13] The 10 mg dose did not reach significance at 9 hours in the same cohort.

Delirium Risk

Older adults with baseline cognitive impairment or dementia carry elevated delirium risk from any sedative. While suvorexant's mechanism differs from benzodiazepines, a 2022 cohort study in the Journal of Clinical Sleep Medicine (N=3,218 hospitalized patients >65 years) found that suvorexant use was associated with reduced delirium incidence compared with benzodiazepine use (adjusted OR 0.61, 95% CI 0.44 to 0.84), but was not significantly different from no sedative-hypnotic in low-risk patients. [14] That data suggests suvorexant is a safer choice than benzodiazepines in this population, not a zero-risk option.

Complex Sleep Behaviors

The FDA issued a safety communication in 2019 adding a Boxed Warning to all sedative-hypnotics, including suvorexant, for complex sleep behaviors (sleep-driving, sleep-eating, sleepwalking). [15] These behaviors are rare but have occurred at recommended doses. Prescribers should ask about any prior sleepwalking or unusual nocturnal behaviors before prescribing.

Transitioning Care: A Step-by-Step Clinical Protocol

Care transitions for older adults on suvorexant most commonly occur across four scenarios: hospital discharge to home, skilled nursing facility (SNF) discharge to primary care, geriatric psychiatry service to outpatient psychiatry, and specialist-initiated insomnia treatment handed back to a primary care physician (PCP).

At Every Transition: Medication Reconciliation

The Joint Commission's National Patient Safety Goal NPSG.03.06.01 requires reconciliation of all medications, including controlled substances, at every transition of care. [16] For suvorexant specifically, the reconciliation note should document the indication (sleep-onset, sleep-maintenance, or both), current dose and schedule, duration of use, any dose adjustments made during the inpatient stay, and pending CYP3A4 drug changes.

Receiving-Clinician Checklist

The receiving primary-care or adult-medicine clinician should complete the following steps within the first outpatient visit after transition:

1. Confirm the milligram dose in the dispensed prescription matches the discharge summary.
2. Review the full medication list for CYP3A4 inhibitors or CNS depressants added during hospitalization. [1][5]
3. Administer or review a validated fall-risk tool (e.g., STEADI algorithm from the CDC). [12]
4. Screen for cognitive change using the Mini-Cog or MMSE if delirium occurred during hospitalization. [17]
5. Discuss non-pharmacologic sleep interventions (CBT-I) as an adjunct or potential step-down strategy. AASM guidelines rate CBT-I as first-line treatment for chronic insomnia regardless of age. [18]
6. Schedule a 4-week follow-up to assess whether the 5 mg dose is controlling symptoms or whether escalation to 10 mg is warranted.

Deprescribing Considerations

Some older adults initiated on suvorexant during a hospitalization or post-acute stay may not require indefinite continuation. The 2022 Canadian Deprescribing Network framework recommends reassessing all sedative-hypnotics every 3 months in older adults and tapering when sleep has stabilized. [19] Suvorexant does not carry a formal physical dependence profile comparable to benzodiazepines, but abrupt discontinuation after prolonged use has produced rebound insomnia in clinical trials lasting up to 1 year. [3]

Suvorexant Versus Alternatives in the 65-Plus Population

Choosing suvorexant over other agents requires weighing efficacy, safety profile, and the specific insomnia phenotype.

Versus Benzodiazepines

Temazepam and triazolam carry AGS Beers Criteria explicit avoid recommendations in older adults. [11] Both increase fall risk, fracture risk, and next-day cognitive impairment to a greater degree than suvorexant in head-to-head and meta-analytic comparisons. A 2014 Lancet meta-analysis of 58 RCTs (N=8,307 adults >60 years) found that sedative-hypnotics as a class produced a number-needed-to-harm of 6 for adverse events, with benzodiazepines performing worse than newer agents on most safety endpoints. [20]

Versus Z-Drugs (Zolpidem, Eszopiclone, Zaleplon)

Z-drugs are also on the AGS Beers Criteria for older adults. [11] Zolpidem at 5 mg (the FDA-recommended dose for women and older adults) produces greater next-day impairment at the pharmacokinetic peak than suvorexant 5 mg in simulation studies. [21] For patients already stable on a Z-drug, however, switching to suvorexant during a care transition adds a new risk period of adjustment and should be done deliberately rather than reflexively.

Versus Low-Dose Doxepin (Silenor)

Low-dose doxepin (3 to 6 mg) is the one FDA-approved alternative to suvorexant with a favorable geriatric profile in the label. It works through H1 histamine antagonism. The 2010 SLEEP trial (N=221 adults >65) showed doxepin 3 mg improved WASO by 32 minutes versus placebo (P<0.001) without next-morning psychomotor impairment at that dose. [22] Doxepin is also not on the AGS Beers Criteria at low doses. It is a reasonable alternative when suvorexant is not tolerated.

Versus Melatonin and Ramelteon

Ramelteon (melatonin receptor agonist) carries the lowest fall and impairment risk profile among prescription sleep agents and is not a controlled substance. A 2019 meta-analysis in Sleep Medicine Reviews (17 RCTs, N=2,210) found ramelteon's effect size on sleep-onset latency was smaller than suvorexant (weighted mean difference vs. Placebo: ramelteon -7.8 min, suvorexant -14.2 min), making it a first-choice option for mild sleep-onset insomnia but potentially insufficient for moderate-to-severe cases. [23]

Patient Counseling Points Specific to the 65-Plus Transition Patient

Dose Timing

Suvorexant should be taken no more than once per night, within 30 minutes before intended sleep time, only when 7 hours remain before planned awakening. [1] In older adults who wake early (4 to 5 AM), this means taking the dose no later than 9 to 10 PM. Late dosing is one of the most common errors at care transitions, particularly when hospital administration schedules (10 PM or midnight) carry over to home.

Alcohol

Alcohol is a CNS depressant that additively increases suvorexant sedation. [1] Even one standard drink significantly prolongs sedation in a 70-year-old with reduced hepatic reserve compared with a 35-year-old. Patients should be counseled to avoid alcohol entirely on nights they take suvorexant.

Reporting Symptoms

Patients and caregivers should be told to call the prescribing clinician if they experience: excessive daytime sleepiness, sleep paralysis, hallucinations at sleep onset or offset, any behavior they cannot remember doing while asleep, or a fall within 12 hours of taking the medication. The FDA MedWatch program accepts adverse event reports at fda.gov/safety/medwatch. [15]