Insomnia, a highly prevalent disorder, can be detrimental to patients' overall 
health and worsen existing comorbidities. Patients may have acute episodes of 
insomnia related to a traumatic event, but more commonly insomnia occurs 
chronically. While proper sleep hygiene and behavioral therapy play important 
roles in the nonpharmacologic management of short-term and chronic insomnia, 
medications may also be required. Historically, insomnia has been treated with 
agents such as benzodiazepines, nonbenzodiazepine receptor agonists, and 
melatonin agonists. Dual orexin receptor antagonists represent a new class of 
medications for the treatment of insomnia, which block the binding of 
wakefulness-promoting neuropeptides orexin A and orexin B to their respective 
receptor sites. Suvorexant (Belsomra) is the first dual orexin receptor 
antagonist to be approved in the US and Japan and has demonstrated efficacy in 
decreasing time to sleep onset and increasing total sleep time. Its unique 
mechanism of action, data to support efficacy and safety over 12 months of use, 
and relative lack of withdrawal effects when discontinued may represent an 
alternative for patients with chronic insomnia who cannot tolerate or do not 
receive benefit from more traditional sleep agents. Suvorexant is effective and 
well tolerated, but precautions exist for certain patient populations, including 
females, obese patients, and those with respiratory disease. Suvorexant has only 
been studied vs placebo, and hence it is unknown how it directly compares with 
other medications approved by the US Food and Drug Administration for insomnia. 
Suvorexant is not likely to replace benzodiazepines or nonbenzodiazepine 
receptor antagonists as a first-line sleep agent but does represent a novel 
option for the treatment of patients with chronic insomnia.