title: 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.
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Hwa Sik
authors.initials: HS
authors.lastname: Jung
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Chan-Ho
authors.initials: CH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Young Tae
authors.initials: YT
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Mi Ae
authors.initials: MA
authors.lastname: Bae
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Youn Im
authors.initials: YI
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Byung Ju
authors.initials: BJ
authors.lastname: Kang
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Yangjin
authors.initials: Y
authors.lastname: Jegal
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Jong Joon
authors.initials: JJ
authors.lastname: Ahn
authors.affiliation: Department of Internal Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan 682-714, Korea.
authors.forename: Taehoon
authors.initials: T
authors.lastname: Lee
keywords: Anaphylaxis; Gynecomastia; Histamine H1 Antagonists