Purpose: The safety and efficacy of quetiapine for the treatment of insomnia in adults are reviewed.
Summary: Quetiapine was developed for the treatment of psychiatric disorders, but its antagonism of histamine H1- and serotonin type 2A receptors has the added effect of causing sedation. As such, quetiapine is widely used off-label as a treatment for insomnia. Due to quetiapine's potential adverse effects, guidelines for the treatment of insomnia have recommended the drug's use only in patients with specific comorbid psychiatric disorders. The use of quetiapine for the treatment of insomnia in the absence of comorbid conditions has been evaluated in only two clinical trials of 31 patients in total, and very few studies have evaluated quetiapine use in patients with insomnia and other comorbidities. No trials have been conducted comparing quetiapine with an active control (e.g., zolpidem); the data that exist compare quetiapine to a placebo or there is no comparison and all patients are treated with quetiapine. Very few studies have evaluated quetiapine's efficacy in the treatment of insomnia using sleep objective testing, another limitation of the available data on quetiapine.
Conclusion: Robust studies evaluating the safety and efficacy of quetiapine for the treatment of insomnia are lacking. Given its limited efficacy data, its adverse-effect profile, and the availability of agents approved by the Food and Drug Administration for the treatment of insomnia, quetiapine's benefit in the treatment of insomnia has not been proven to outweigh potential risks, even in patients with a comorbid labeled indication for quetiapine.