Efficacy and tolerability of second- and third-generation antihistamines in the treatment of acquired cold urticaria: a meta-analysis

Background Acquired cold urticaria (ACU) is a form of physical urticaria that has been treated with first-generation antihistamines; there is a paucity of data regarding second- and third-generation antihistamines for the treatment of ACU. Objective To perform a systematic review of the literature to determine the efficacy of second- and third-generation antihistamines in the treatment of ACU. Methods Data were extracted via a MEDLINE search of the literature between 1950 and May 2009. We included double-blind, randomized, placebo-controlled studies comparing the treatment of patients with ACU with second- and third-generation antihistamine medications vs placebo. Results Overall, 98 patients were identified from 4 included studies. Two trials indicated that second- and third-generation antihistamines significantly eliminated the presence of wheals after treatment vs placebo (odds ratio [OR], 8.88; 95% confidence interval [CI], 4.35 to 18.13). Two trials demonstrated a reduction in wheal area after treatment with a second- or third-generation antihistamine compared with placebo (mean difference, −347.99 mm2 ; 95% CI, −489.43 to −206.54 mm2 ). Two trials demonstrated significant elimination of pruritus with second- or third-generation antihistamine treatment vs placebo (OR, 10.44; 95% CI, 4.39 to 24.84). All 4 studies assessed the tolerability of a second- or third-generation antihistamine vs placebo and found an increased rate of adverse events (OR, 3.04; 95% CI, 1.53 to 6.06), although the complaints were mild. Conclusions The newer, less-sedating antihistamines seem to be effective in the treatment of ACU in terms of their ability to significantly reduce the presence of wheals and pruritus after cold exposure. These medications are usually well tolerated, with only mild adverse effects.