Pharmacoepidemiol Risk Manage.  2023 Mar;15(1):32-40. 10.56142/perm.23.0007.

An Overview on the Adverse Reactions of H1-Antihistamine

• Ahn KM
• Kim HJ
• Kang HR

• KMID: 2544375
• DOI: http://doi.org/10.56142/perm.23.0007

Abstract

Histamine is one of the most essential biochemical molecules involved in various responses, including inflammation, neurotransmission, and cell proliferation, in diverse organs. Clinical manifestations of allergic diseases are often triggered or initiated by histamine. In order to prevent histamine reactions in allergic disease, clinicians have attempted to develop antagonist of histamine receptors. Due to its effectiveness, antihistamine has been widely used in the treatment of allergic diseases, such as allergic rhinitis and urticaria by inhibiting histamine actions. Although antihistamines are generally safe, there are patients who experience unexpected side effects, such as sedation, cardiotoxicity, hepatotoxicity, nephrotoxicity, and change of appetite. Due to their ability to penetrate through blood-brain barrier, first-generation antihistamines potentially impair alertness, cognition, and memory. The safety profiles of the second-generation antihistamines are relatively superior to the first-generation antihistamines; the second-generation antihistamines cause relatively less central nervous system adverse reactions. However, serious cardiotoxicity of early second-generation antihistamines, such as terfenadine and astemizole, was reported. Moreover, widely-used second-generation antihistamine, cetirizine and loratadine, can present hepatotoxicity. In addition, body weight gain caused by both first- and second-generation antihistamines had been reported. In recent decades, pharmacologic mechanisms that are involved in these sides effect of antihistamine have been elucidated. Understanding detailed mechanisms and consequences of commonly observed side effects may help clinicians prescribe antihistamines safely. Herein, we summarize the mechanisms of histamine action, roles of antihistamines, and their common side effects in order to provide better understanding of antihistamines in clinical practice. (PeRM 2023;15:32-40)

Keyword

Histamine antagonist; Adverse effect; Sedation; Cardiotoxicity; Hepatotoxicity; Nephrotoxicity