Comparison of levocetirizine up-dosing versus combination of levocetrizine and desloratidine in chronic urticaria not responding to standard levocetrizine dose: An open-label parallel-arm randomized controlled trial

Chronic urticaria isa common disease affecting 0.5% to 1% of individuals (lifetime prevalence).Management of the disease still remains unclear despite multiple clinicaltrials. Second-generation H1-antihistamines are recommended as first-linetherapy; the choice and doses of antihistamines and associated drugs are notspecified. The EAACI/GA2LEN/EDF/WAO guidelines recommend increasing the dose ofanti-histaminics up to 4-times in patients non-responding to the conventionaldoses of anti-histamines. Drug-related adverse effects, such as sedation is aconcern with higher doses of the same antihistamine. Combination of twodifferent group of second generation antihistamines may be more efficacious forthe same and associated with less risk of sedation. However, there are no studiescomparing the standard guideline with combination of two second generationantihistamines. So there is need for a clinical trial comparing these tworegimens for effective management of the urticaria not responding to thestandard dose of antihistamine.Given the lack ofcontrolled studies assessing the efficacy and safety of high-dose non-sedatingantihistamines in CU, patient safety should be a key consideration whenchoosing a specific antihistamine. Additionalwell-controlled, well-designed clinical trials in CU are required to clarifywhich non-sedating antihistamines should be used, in what dose, and for howlong, when CU does not respond to standard therapy. Clinical recommendationsregarding the use of first-generation antihistamines, increased dosages ofsecond-generation antihistamines, and third- and fourth-line alternatives forCU are based on incomplete and inconsistent data.