Gynecomastia induced by H1-antihistamine (ebastine) in a patient with idiopathic anaphylaxis

Abstract

H1-antihistamine is generally a well-tolerated and safe drug. However, in resemblance with all other drugs, H1-antihistamines can also prompt adverse drug reactions (ADRs). We recently encountered the very unusual ADR of H1-antihistamine-induced gynecomastia. A 21-year-old man with idiopathic anaphylaxis was treated with ebastine (Ebastel), a second-generation H1-antihistamine, for the prevention of anaphylaxis. Three months later, the patient remained well without anaphylaxis, but had newly developed gynecomastia. Because anaphylaxis recurred after the cessation of H1-antihistamine, the preventive medication was changed to omalizumab. A few months later, his gynecomastia had entirely disappeared. Physicians should be aware of this exceptional ADR of H1-antihistamine.

The sticky relationship between allergies and infections

“…Finally, for daily practice allergists, it is still very difficult to diagnose and aware some rare agents that caused anaphylaxis, such as intravenous tacolimus and cyclosporine [ 16 ], and gynecomastia caused by H1-antihistamine (ebastine) [ 17 ] in the case reported from Korea. Using basophil activation test for in vitro diagnosis of chlorpheniramine-induced anaphylaxis was discussed by Lee et al [ 18 ] in this issue may provide some insights and future resolution in the diagnosis of life-threaten clinical condition of anaphylaxis.…”