Suvorexant is indicated for the treatment of insomnia, characterized by difficulty in falling asleep and/or maintaining sleep.

Suvorexant is a highly selective antagonist of orexin receptors OX1R and OX2R. Its therapeutic effect in insomnia is believed to occur through inhibition of orexin receptor activity. The orexin neuropeptide system plays a key role in promoting wakefulness. By blocking the binding of wake-promoting neuropeptides orexin A and orexin B to OX1R and OX2R receptors, Suvorexant reduces wake drive and facilitates sleep onset and maintenance.

Recommended dose is 10 mg, no more than once per night taken before 30 minutes of going to bed, with at least 7 hours remaining before the planned time of awakening. If the 10 mg dose is well-tolerated but not effective, the dose can be increased, not to exceed 20 mg once daily. Lowest dose effective should be used for the patient. Time to effect may be delayed if taken with or soon after a meal.

CNS-active drugs: An additive effect on psychomotor performance was observed when a single dose of 40 mg suvorexant was co-administered with alcohol (0.7 g/kg). Suvorexant does not affect alcohol levels, and alcohol does not alter suvorexant concentrations.

Effect of other drugs on Suvorexant: Strong CYP3A inhibitors (e.g., ketoconazole, itraconazole) and moderate inhibitors (e.g., diltiazem) significantly increase suvorexant exposure. Strong CYP3A inducers (e.g., rifampin) significantly reduce suvorexant exposure.

Effect of Suvorexant on other drugs: Suvorexant is unlikely to cause clinically significant inhibition of major CYP enzymes (CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6). It is also unlikely to induce metabolism of drugs metabolized by major CYP pathways with chronic use.

Do not use in patients with narcolepsy.

Common side effects include: Daytime drowsiness, Difficulty thinking clearly, Confusion or unusual behavior, Sleepwalking.

Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Suvorexant should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. It is unknown whether it is excreted in human milk; caution is advised during breastfeeding.

Daytime somnolence: May impair alertness and motor coordination, including driving ability; risk increases with higher doses.

Reassessment needed: If insomnia persists after 7–10 days, re-evaluate the patient.

Complex sleep behaviors: Sleep-driving and other activities may occur while not fully awake; risk increases with alcohol or CNS depressants.

Depression/suicidal risk: May worsen depression or suicidal thoughts; monitor behavioral changes and discontinue if necessary.

Miscellaneous sedatives & hypnotics

Store in a cool, dry place, protected from light. Keep out of reach of children.