In a 67-year-old man with sleep‑onset and sleep‑maintenance insomnia who cannot tolerate zolpidem or eszopiclone and for whom benzodiazepines are undesirable, is suvorexant (Belsomra) appropriate, and what starting dose and safety precautions should be used?

Suvorexant is Appropriate for This Patient

Yes, suvorexant (Belsomra) is an appropriate choice for this 67-year-old man with both sleep-onset and sleep-maintenance insomnia who cannot tolerate Z-drugs and should avoid benzodiazepines. Start with 10 mg taken once nightly within 30 minutes of bedtime, with at least 7 hours remaining before planned awakening 1.

Rationale for Suvorexant in This Clinical Scenario

The American Academy of Sleep Medicine (AASM) 2017 guidelines provide a weak for recommendation supporting suvorexant specifically for sleep maintenance insomnia, based on trials using 10,15/20, and 20 mg doses 2. While the recommendation is "weak" in GRADE terminology, this reflects the evidence quality rather than lack of efficacy—suvorexant demonstrated:

• Wake after sleep onset reduction: 16-28 minutes greater than placebo (95% CI: 7 to 43 minutes)
• Total sleep time improvement: 10 minutes longer than placebo (95% CI: 2 to 19 minutes) 2

The 2020 VA/DOD guidelines note "insufficient evidence to recommend for or against" suvorexant 3, but this divergence from AASM likely reflects timing differences in guideline publication and the VA/DOD's focus on military/veteran-specific concerns (combat operations, traumatic brain injury).

Starting Dose and Titration

Start with 10 mg once nightly 1. This is the FDA-recommended starting dose for adults. The FDA label explicitly states:

• If 10 mg is well-tolerated but not effective, increase to maximum 20 mg once nightly
• Take within 30 minutes of bedtime with ≥7 hours remaining before awakening
• Avoid taking with or soon after meals (delays effect) 1

Age-Specific Considerations for a 67-Year-Old

At age 67, this patient falls into the "elderly" category (≥65 years) used in clinical trials. Research specifically in older adults shows suvorexant improves both subjective and polysomnographic sleep parameters and is generally well tolerated 4. A 2026 meta-analysis confirmed efficacy in elderly patients with chronic insomnia 5.

Critical Safety Precautions

CNS Depression and Next-Day Impairment

Warn the patient explicitly about driving impairment risk 1. The FDA label includes a black-box-level warning:

• CNS depressant effects can persist for several days after discontinuation
• Patients on 20 mg should be cautioned against next-day driving
• Even at 10 mg, individual variation in sensitivity exists—monitor for daytime somnolence
• Discontinue or decrease dose if daytime somnolence develops 1

Respiratory Function Monitoring

Exercise caution given the patient's age—assess for any underlying respiratory disease 1. While not contraindicated, suvorexant's effect on respiratory function should be considered, particularly in elderly patients who may have undiagnosed sleep apnea or COPD. Recent pharmacovigilance data show safety signals for dyspnea with suvorexant 6, 7.

Drug Interactions

• Avoid strong CYP3A inhibitors (ketoconazole, itraconazole, clarithromycin, ritonavir)—suvorexant is not recommended with these agents 1
• With moderate CYP3A inhibitors (diltiazem, erythromycin, fluconazole, verapamil): reduce starting dose to 5 mg, maximum 10 mg 1
• Monitor digoxin levels if patient is on digoxin 1

Contraindication

Suvorexant is absolutely contraindicated in narcolepsy 1. Ensure this patient does not have undiagnosed narcolepsy (excessive daytime sleepiness, cataplexy, sleep paralysis).

Advantages Over Other Options in This Patient

Why Suvorexant Over Low-Dose Doxepin?

Both received favorable recommendations from AASM for sleep maintenance 2. However:

• Suvorexant addresses both sleep onset and maintenance in this patient with mixed insomnia
• Doxepin (tricyclic) carries anticholinergic risks particularly concerning in a 67-year-old (urinary retention, confusion, falls)
• Recent evidence suggests doxepin has lower risk of somnolence than suvorexant 6, but the patient's intolerance to Z-drugs suggests he may not tolerate anticholinergic effects

Why Not Ramelteon?

Ramelteon targets only sleep onset, not maintenance 2. This patient has both problems.

Why Not Benzodiazepines?

The question explicitly states benzodiazepines are "undesirable"—appropriately so given:

• Fall risk in elderly
• Cognitive impairment
• Dependence potential
• VA/DOD guidelines include a "weak against" recommendation for benzodiazepines 3

Monitoring and Duration

• Reassess after 7-10 days to evaluate efficacy and tolerability 1
• Suvorexant has been studied safely for up to 12 months 8, 9, 10
• No evidence of rebound insomnia or withdrawal when discontinued after 3 months of nightly use 8, 9
• Monitor for complex sleep behaviors (sleep-walking, sleep-driving)—discontinue immediately if these occur 1

Common Pitfalls to Avoid

1. Don't start at 20 mg—always begin at 10 mg to assess tolerability
2. Don't ignore meal timing—taking with food delays onset of action
3. Don't overlook the 7-hour sleep opportunity requirement—patient must have adequate time in bed
4. Don't miss comorbid sleep apnea—screen for snoring, witnessed apneas, excessive daytime sleepiness before attributing all symptoms to insomnia
5. Don't forget cognitive behavioral therapy for insomnia (CBT-I)—while not the focus of this pharmacologic question, CBT-I remains first-line per guidelines 3