title: A cross-sectional observational study of high override rates of drug allergy alerts in inpatient and outpatient settings, and opportunities for improvement.
abstract: To evaluate how often and why providers overrode drug allergy alerts in both the inpatient and outpatient settings.
  
  
  
  A cross-sectional observational study of drug allergy alerts generated over a 3-year period between 1 January 2009 and 31 December 2011.
  
  
  
  A 793-bed tertiary care teaching affiliate of Harvard Medical School and 36 primary care practices.
  
  
  
  Drug allergy alerts were displayed for a total of 29 420 patients across both settings.
  
  
  
  Proportion of drug allergy alerts displayed and overridden, proportion of appropriate overrides, proportion of overrides in each medication class, different reasons for overriding and types of reactions overridden.
  
  
  
  A total of 158 023 drug allergy alerts were displayed, 131 615 (83%) in the inpatient setting and 26 408 (17%) in the outpatient setting; 128 157 (81%) of which were overridden. A random sample of inpatient (n=200, 0.19%) and outpatient (n=50, 0.25%) alert overrides were screened for appropriateness, with >96% considered appropriate. Alerts for some drug classes, such as 'non-antibiotic sulfonamides', were overridden for >81% of prescriptions in both settings. The most common override reason waspatient has taken previously without allergic reaction. In the inpatient setting alone, 70.9% of alerts that warned against the risk ofanaphylaxiswere overridden.
  
  
  
  The information contained in patients' drug allergy lists needs to be regularly updated. Most of the drug allergy alerts were overridden, with the majority of alert overrides in the subsample considered appropriate. Some of the rules for these alerts should be carefully reviewed and modified, or removed. Further research is needed to understand providers' overriding of alerts that warned against the risk of 'anaphylaxis', which are more concerning with respect to patient safety.
authors.affiliation: Department of Pharmacy Practice, Durham University, Durham, UK.
authors.forename: Sarah Patricia
authors.initials: SP
authors.lastname: Slight
authors.affiliation: Research Center for Medical Informatics, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Patrick E
authors.initials: PE
authors.lastname: Beeler
authors.affiliation: Research Center for Medical Informatics, Partners Healthcare, Boston, Massachusetts, USA.
authors.forename: Diane L
authors.initials: DL
authors.lastname: Seger
authors.affiliation: Department of Pharmacy, MCPHS University, Boston, Massachusetts, USA.|Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Mary G
authors.initials: MG
authors.lastname: Amato
authors.affiliation: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Qoua L
authors.initials: QL
authors.lastname: Her
authors.affiliation: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Swerdloff
authors.affiliation: Louvain Drug Research Institute, Universite catholique de Louvain (UCL), Belgium, Belgium.
authors.forename: Olivia
authors.initials: O
authors.lastname: Dalleur
authors.affiliation: Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, USA.
authors.forename: Karen C
authors.initials: KC
authors.lastname: Nanji
authors.affiliation: Department of Nursing, Inha University, Incheon, Korea, Republic of.|Public Health Department, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: InSook
authors.initials: I
authors.lastname: Cho
authors.affiliation: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Nivethietha
authors.initials: N
authors.lastname: Maniam
authors.affiliation: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Tewodros
authors.initials: T
authors.lastname: Eguale
authors.affiliation: Division of General Internal Medicine and Primary Care, Partners Healthcare, Boston, Massachusetts, USA.
authors.forename: Julie M
authors.initials: JM
authors.lastname: Fiskio
authors.affiliation: Division of General Internal Medicine & Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Patricia C
authors.initials: PC
authors.lastname: Dykes
authors.affiliation: Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Bates
mesh_terms: D000554:Ambulatory Care Facilities; D056902:Clinical Alarms / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D003657:Decision Making; D004342:Drug Hypersensitivity; D006760:Hospitalization; D058996:Quality Improvement
keywords: Decision support, computerized; Health services research; Medication safety