Is suvorexant (Belsomra) safe to use in patients with chronic respiratory failure?

Safety of Suvorexant in Chronic Respiratory Failure

Suvorexant should be used with caution in patients with chronic respiratory failure, as the FDA label specifically warns about considering respiratory effects in patients with compromised respiratory function. 1

Evidence on Respiratory Effects

FDA Labeling and Warnings

The FDA label for suvorexant (Belsomra) clearly states that "Effect of BELSOMRA on respiratory function should be considered if prescribed to patients with compromised respiratory function" and notes that it "has not been studied in patients with severe obstructive sleep apnea (OSA) or severe chronic obstructive pulmonary disease (COPD)." 1

Research Evidence

Several studies have investigated suvorexant's respiratory effects:

• A randomized, double-blind, placebo-controlled study in patients with mild-to-moderate COPD found no clinically significant effect on mean oxygen saturation (SpO2) or meaningful increase in Apnea Hypopnea Index (AHI) with suvorexant doses of 30-40 mg (higher than the maximum recommended dose of 20 mg) 2

• In patients with mild-to-moderate OSA, suvorexant 40 mg showed a small increase in mean AHI after multiple doses but no effect on mean SpO2 3

• In healthy subjects, suvorexant at doses up to 150 mg showed no significant effects on respiration during sleep 4

Clinical Decision Making

Risk Assessment

When considering suvorexant for patients with chronic respiratory failure:

1. Severity of respiratory compromise:

   • The medication has not been studied in severe COPD or severe OSA 1
   • Available studies only included patients with mild-to-moderate respiratory conditions 2, 3

2. Dose considerations:

   • Lower doses (5-10 mg) may be preferable for initial treatment
   • The maximum approved dose in the US is 20 mg 1
   • Studies showing respiratory safety used doses of 30-40 mg 2

3. Patient monitoring:

   • Consider baseline oxygen saturation monitoring
   • Be alert for worsening respiratory symptoms
   • Monitor for next-day impairment, which may be more pronounced in patients with respiratory conditions

Precautions and Contraindications

• CNS depression: Suvorexant is a CNS depressant and may have additive effects with other respiratory depressants 1

• Concomitant medications: Avoid combining with other CNS depressants when possible, as this may increase respiratory depression risk 1

• Patient education: Advise patients about potential next-day impairment and increased risk of falls, which may be particularly important in patients with respiratory conditions 1

Alternative Approaches

For patients with chronic respiratory failure requiring treatment for insomnia:

• Consider non-pharmacological approaches first (sleep hygiene, cognitive behavioral therapy for insomnia)

• If medication is necessary, start with the lowest effective dose of suvorexant

• Consider respiratory monitoring during initial treatment in high-risk patients

Conclusion

While suvorexant appears to have a relatively favorable respiratory safety profile compared to some other sedative-hypnotics based on studies in patients with mild-to-moderate respiratory conditions 2, 3, caution is warranted in patients with chronic respiratory failure. The decision to use suvorexant should balance the potential benefits for sleep against the theoretical risks of respiratory depression, with careful consideration of dosing and monitoring.