Most of the second-generation anti-histamines with no-somnolence and no-cardiotoxic, such as fexofenadine, have demonstrated their healthy properties in drug-interaction studies, elevated-dose experiments, and clinical trials including pediatric and elderly patients. Nevertheless, in new H1R antihistamines, potential potassium channel interactions are only beginning to be studied . Many questions still remain on possible crossreactivities with other HRs and/or potassium channels, therefore, new highly specific H1R antihistamines with reduced out-of-target effects continue to be searched .