title: α1-Adrenergic receptor antagonists and gynecomastia. A case series from the Italian spontaneous reporting system and VigiBase(™).
abstract: OBJECTIVE
  The aim of this study was to analyze the cases of gynecomastia associated with α1A-adrenergic receptor antagonists (α1-ARAs) in the Italian spontaneous reporting system database (Rete Nazionale di Farmacovigilanza or RNF) and in the World Health Organization ICSRs database (VigiBase(™)), focusing on tamsulosin use.
  
  
  METHODS
  We analyzed the spontaneous reports of gynecomastia related to the use of α1-ARAs and collected from the RNF and from VigiBase(™) up to December 2012. Cases of gynecomastia have been defined as reports associated with gynecomastia according with Medical Dictionary for Regulatory Activities (MedDRA). Reporting odds ratio (ROR) and Information Component (IC) were calculated as measures of disproportionality in RNF and VigiBase(™), respectively.
  
  
  RESULTS
  Up to December 2012, about 186,000 reports were recorded in the RNF. Among these, 902 reports of adverse drug reaction (ADR) have been associated with the use of at least one α1-ARAs. Of these, in 15 cases, gynecomastia was a listed ADR: in 10, the suspected drug was tamsulosin (in eight, it was the sole suspect); in two, doxazosin and alfuzosin, respectively; and in one, terazosin. ROR for tamsulosin was 5.3 (95% CI 1.8, 15.7). In VigiBase(™), 84 reports of gynecomastia indicated tamsulosin as suspected drug. Tamsulosin-associated gynecomastia showed the highest IC value within this class of drugs (IC 95% 2.43).
  
  
  CONCLUSIONS
  In this study, we highlight a possible association between gynecomastia and tamsulosin use. To our knowledge, this association has not been described before and could represent a potential signal.
authors.affiliation: Pharmacology Unit and Pharmacovigilance Centre of Veneto Region, University Hospital, P.le L.A. Scuro, 10, 37134, Verona, Italy, ermelinda.viola@univr.it.
authors.forename: Ermelinda
authors.initials: E
authors.lastname: Viola
authors.forename: Sibilla
authors.initials: S
authors.lastname: Opri
authors.forename: Ugo
authors.initials: U
authors.lastname: Moretti
authors.forename: Roberto
authors.initials: R
authors.lastname: Leone
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Casini
authors.forename: Sara
authors.initials: S
authors.lastname: Ruggieri
authors.forename: Claudia
authors.initials: C
authors.lastname: Minore
authors.forename: Anita
authors.initials: A
authors.lastname: Conforti
mesh_terms: D058668:Adrenergic alpha-1 Receptor Antagonists / Q000009:adverse effects*; D000328:Adult; D016907:Adverse Drug Reaction Reporting Systems / Q000706:statistics & numerical data*; D000368:Aged; D000369:Aged, 80 and over; D006177:Gynecomastia / Q000139:chemically induced*; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D013449:Sulfonamides / Q000009:adverse effects; D000077409:Tamsulosin
chemical_list: D058668:Adrenergic alpha-1 Receptor Antagonists; D013449:Sulfonamides; D000077409:Tamsulosin