H1-antihistamines for chronic spontaneous urticaria: an abridged Cochrane Systematic Review.
BACKGROUND: Chronic spontaneous urticaria is characterized by recurrent itchy wheals. First-line management is with H1-antihistamines. OBJECTIVE: We sought to conduct a Cochrane Review of H1-antihistamines in the treatment of chronic spontaneous urticaria. METHODS: A systematic search of major databases for randomized controlled trials was conducted. RESULTS: We included 73 studies with 9759 participants; 34 studies provided outcome data for 23 comparisons. Compared with placebo, cetirizine 10 mg daily in the short and intermediate term (RR 2.72; 95% confidence interval [CI] 1.51-4.91) led to complete suppression of urticaria. Levocetirizine 20 mg daily was effective for short-term use (RR 20.87; 95% CI 1.37-317.60) as was 5 mg for intermediate-term use (RR 52.88; 95% CI 3.31-843.81). Desloratadine 20 mg was effective for the short term (RR 15.97; 95% CI 1.04-245.04) as was 5 mg in the intermediate term (RR 37.00; 95% CI 2.31-593.70). There was no evidence to suggest difference in adverse event rates between treatments. LIMITATIONS: Some methodological limitations were observed. Few studies for each comparison reported outcome data that could be incorporated in meta-analyses. CONCLUSIONS: At standard doses, several antihistamines are effective and safe in complete suppression of chronic spontaneous urticaria. Research on long-term treatment using standardized outcome measures and quality of life scores is needed.