Impact of β-Lactam Allergies on Antimicrobial Selection in an Outpatient Setting

South Med J. 2019 Nov;112(11):591-597. doi: 10.14423/SMJ.0000000000001037.

Abstract

Objective: The primary objective of this study was to determine whether patients prescribed nonpreferred antibiotics received appropriate alternative antibiotics.

Methods: This was a retrospective observational analysis of military veteran patients with a β-lactam allergy treated in an outpatient clinic or emergency department for an infection during a 5-year span. Antibiotic regimens were first stratified as preferred or nonpreferred based on infection-specific guidelines. The nonpreferred regimens were then evaluated for appropriateness based on allergy history and culture and sensitivity reports.

Results: Of 445 fills of antibiotics evaluated, 269 met inclusion criteria, comprising 253 unique infections in 80 patients. Patients received nonpreferred antibiotics for their infection type in 57% of cases. Of the nonpreferred antibiotics, 56% were inappropriate based on guideline-recommended alternatives, allergy history, and culture and sensitivity data. Of the 88 allergies, 97% were historical/self-reported and 48% were cutaneous. In addition, 39% of patients safely received β-lactam antibiotics after documentation of their allergy.

Conclusions: Patients with documented β-lactam allergies are at high risk of receiving nonpreferred and inappropriate antibiotics, and many reactions likely do not reflect true allergies. These data emphasize the negative impact of the "β-lactam allergy" label and the importance of reassessing allergies.

Publication types

  • Observational Study

MeSH terms

  • Aged
  • Anti-Bacterial Agents / adverse effects*
  • Anti-Bacterial Agents / therapeutic use
  • Drug Hypersensitivity / etiology*
  • Drug Prescriptions / statistics & numerical data*
  • Emergency Service, Hospital
  • Female
  • Humans
  • Inappropriate Prescribing / statistics & numerical data*
  • Male
  • Outpatient Clinics, Hospital
  • Retrospective Studies
  • Tennessee
  • Veterans
  • Veterans Health Services
  • beta-Lactams / adverse effects*

Substances

  • Anti-Bacterial Agents
  • beta-Lactams