Cardiac safety of second-generation H1-antihistamines when updosed in chronic spontaneous urticaria

This is a review where the mechanisms and assessment of potential cardiotoxicity of H1-antihistamines are discussed when updosed to four-times their licensed dose. Second generation H1-antihistamines are the primary treatment of chronic urticaria, however there are patients who don’t respond to licensed doses of H1-antihistamines. Current EAACI/GA2LEN/EDF/WAO guideline for urticaria suggest updosing of H1-antihistamines up to 4-fold.

Due to the off label use of this updosing, it is important to ensure its safety. An important aspect of safety is potential cardiotoxicity. This review considered in detail H1-antihistamines such as bilastine, cetirizine, levocetirizine, ebastine, fexofenadine, loratadine, desloratadine, mizolastine and rupatadine. Provided that prescribers carefully considered and ruled out potential risk factors for cardiotoxicity, such as the presence of inherited long QT syndrome, older age, cardiovascular disorders, hypokalemia and hypomagnesemia, or the use of drugs that either haver direct QT prolonging effect or inhibit H1-antihistamines metabolism, reviewers were able to conclude that at up to four-fold the standard dose, H1-antihistamines have excellent cardiac safety profiles.

This is a review where the mechanisms and assessment of potential cardiotoxicity of H1-antihistamines are discussed when updosed to four-times their licensed dose. Second generation H1-antihistamines are the primary treatment of chronic urticaria, however there are patients who don’t respond to licensed doses of H1-antihistamines. Current EAACI/GA2LEN/EDF/WAO guideline for urticaria suggest updosing of H1-antihistamines up to 4-fold.

Due to the off label use of this updosing, it is important to ensure its safety. An important aspect of safety is potential cardiotoxicity. This review considered in detail H1-antihistamines such as bilastine, cetirizine, levocetirizine, ebastine, fexofenadine, loratadine, desloratadine, mizolastine and rupatadine. Provided that prescribers carefully considered and ruled out potential risk factors for cardiotoxicity, such as the presence of inherited long QT syndrome, older age, cardiovascular disorders, hypokalemia and hypomagnesemia, or the use of drugs that either haver direct QT prolonging effect or inhibit H1-antihistamines metabolism, reviewers were able to conclude that at up to four-fold the standard dose, H1-antihistamines have excellent cardiac safety profiles.