Trazodone for Insomnia: A Systematic Review

OBJECTIVE: While trazodone is approved for the treatment of depression, the off-label use of this medication for insomnia has surpassed its usage as an antidepressant. In this systematic review, we examined the evidence for the efficacy and safety of trazodone for insomnia. METHODS: A literature search was conducted using MEDLINE/PubMed databases from the past 33 years (1983-2016) and the keywords insomnia, trazodone, sedative, treatment, and hypnotics. The results were restricted to English language and human subjects. All randomized clinical trials, meta-analyses, observational studies, and placebo-controlled trials regarding trazodone for the treatment of primary or secondary insomnia were reported, per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The study selection process yielded a total of 45 studies. RESULTS: Evidence for the efficacy of trazodone has been repeatedly demonstrated for primary insomnia, as well as secondary insomnia, including for symptoms that are a result of depression, dementia, and being a healthy man. Earlier studies (1980-2000) focused on utilizing trazodone at high doses (≥100mg/d) for the treatment of insomnia among the depressed population; however, since the 2000s, the utility of trazodone has been expanded to treat secondary insomnia among the non-depressed population as well. The side effects are dose-dependent, and the most common is drowsiness. CONCLUSION: A review of the literature suggests that there are adequate data supporting the efficacy and general safety of the low-dose use of trazodone for the treatment of insomnia.