Efficacy and safety of hydroxyzine for sleep in adults: Systematic review

The purpose of this systematic review is to assess the efficacy and safety of hydroxyzine for insomnia in adults.

A comprehensive literature search of PubMed, Embase, and CENTRAL databases was conducted to identify relevant published studies through October 2022 using the search terms: hydroxyzine and sleep, insomnia, sleep disorder or sleep initiation and maintenance disorders. Studies identified for review included prospective, interventional designs or cohort trials that reported impact of hydroxyzine on sleep in adults. Animal studies, case reports, non-English articles, letters to the editor, case studies, and conference abstracts were excluded. Data were extracted using a standardized systematic process.

Five articles were identified for inclusion, including 1 open-label and 4 randomized controlled trials, evaluating a total of 207 patients receiving hydroxyzine 25 mg, 50 mg, or 100 mg at bedtime. Mixed efficacy was demonstrated in the sleep measures of sleep onset, sleep maintenance, and sleep quality. The most common adverse drug effect was dry mouth, although 4 of the 5 studies did not report safety outcomes.

The studies in this review suggest hydroxyzine could be considered as a short-term treatment option for adults with insomnia for whom previous therapy was ineffective, not tolerated, or contraindicated. Additional long-term studies with an active comparator are needed to further establish its role in insomnia treatment.