soo-voe-REX-ant

Therapeutic Classification: sedative/hypnotics

Pharmacologic Classification: orexin receptor antagonists

• Insomnia associated with difficulty in sleep onset and/or maintenance.

• Antagonizes the effects of orexins A and B, naturally occurring neuropeptides that promote wakefulness, by binding to their receptors.

• Improved sleep.

Absorption: 82% absorbed following oral administration; a high-fat meal will delay absorption and sleep onset. ↑ absorption in obese females.

Distribution: Well distributed to tissues.

Protein Binding: >99%.

Metabolism/Excretion: Extensively metabolized by the liver via the CYP3A isoenzyme and to a lesser extent by the CYP2C19 isoenzyme to inactive metabolites. 66% excreted in feces, 23% in urine, mostly as metabolites.

Half-life: 12 hr (↑ in hepatic impairment).

(sleep)

†Excess sedation may persist for several days after discontinuation.

Contraindicated in:

• Narcolepsy
• Severe hepatic impairment.

Use Cautiously in:

• History of substance abuse or drug dependence
• Obese patients (↑ levels, especially in women, dose ↓ may be warranted)
• History of or concurrent psychiatric diagnoses
• Underlying pulmonary disease
• OB: Use during pregnancy only if potential maternal benefit justifies potential fetal risk
• Lactation: Use while breastfeeding only if potential maternal benefit justifies potential risk to infant
• Pedi: Safety and effectiveness not established in children
• Geri: ↑risk of falls in older adults.

Adverse reactions, especially related to CNS depression are dose-related, especially at the 20-mg dose

Neuro: drowsiness, cataplexy, complex sleep behaviors (including sleep driving, sleep walking, or engaging in other activities while sleeping), daytime drowsiness, hallucinations (during sleep), sleep paralysis, worsening of depression/suicidal ideation.

Drug-Drug:

• Strong CYP3A inhibitors, including clarithromycin, conivaptan, itraconazole, ketoconazole, nefazodone, nelfinavir, posaconazole, and ritonavir, ↑ risk of excessive sedation; avoid concurrent use.
• Moderate CYP3A inhibitors, including aprepitant, atazanavir, ciprofloxacin, diltiazem, erythromycin, fluconazole, fosamprenavir, imatinib, and verapamil, may result in ↑ sedation; ↓ suvorexant dose.
• Risk of CNS depression, next-day impairment, "sleep-driving," and other complex behaviors while not fully awake ↑ with other CNS depressants, including alcohol, some antihistamines, opioids, other sedative/hypnotics (including benzodiazepines), and tricyclic antidepressants; dose adjustments may be necessary.
• CYP3A inducers, including carbamazepine, phenytoin, and rifampin, may ↓ levels and effectiveness.
• May alter digoxin levels; closely monitor serum digoxin concentrations.

Drug-Food:

• Grapefruit juice may ↑ levels and excess sedation; ↓ suvorexant dose.

• PO (Adults): 10 mg within 30 min of going to bed; if well tolerated but not optimally effective, dose may be ↑ the following night, not to exceed 20 mg (dose may not be repeated on a single night and should be when 7 hr of sleep time is anticipated before planned awakening). Concurrent use of moderate CYP3A inhibitors: 5 mg initially, dose may be ↑ to 10 mg if lower dose is tolerated but not optimally effective. Lowest effective dose should be used.

• Tablets: 5 mg; 10 mg; 15 mg; 20 mg;

• Assess mental status, sleep patterns, and potential for abuse prior to administration. Prolonged use of >7–10 days may lead to physical and psychological dependence. Limit amount of drug available to the patient.
• Assess alertness at time of peak effect. Notify health care professional if desired sedation does not occur.

• Before administering, reduce external stimuli and provide comfort measures to increase effectiveness of medication.
  • Protect patient from injury. Raise bed side rails. Assist with ambulation. Remove patient’s cigarettes.
  • Use lowest effective dose.
• PO: Administer no more than once/night and within 30 min of going to bed. Take only if at least 7 hr remaining before awaking. DNC: Swallow tablets whole with full glass of water. For faster onset of sleep, do not administer with or immediately after a meal.

• Instruct patient to take suvorexant as directed. Advise patient not to take suvorexant unless able to stay in bed a full night (7 hr) before being active again. Do not take more than the amount prescribed because of the habit-forming potential. Not recommended for use longer than 7–10 days. Instruct patient to read the Medication Guide for correct product before taking and with each Rx refill, changes may occur.
• Because of rapid onset, advise patient to go to bed immediately after taking suvorexant.
• May cause daytime drowsiness or dizziness. Advise patient to avoid driving or other activities requiring alertness for at least 8 hr after dosing until response to this medication is known.
• Caution patient that complex sleep-related behaviors (sleep-driving) may occur while asleep. Inform families and advise to notify health care professional if these behaviors occur.
• Instruct patient to notify health care professional of all Rx or OTC medications, vitamins, or herbal products being taken and to avoid concurrent use of Rx, OTC, and herbal products without consulting health care professional.
• Caution patient to avoid concurrent use of alcohol or other CNS depressants, including opioids.
• Advise patient to notify health care professional if depression worsens or suicidal thoughts occur.
• Advise patient to notify health care professional immediately if signs of anaphylaxis (swelling of the tongue or throat, trouble breathing, and nausea and vomiting) occur.
• Advise females of reproductive potential to notify health care professional if pregnancy is planned or suspected or if breastfeeding.

• Relief of insomnia.

Belsomra

Schedule IV (C-IV)