title: Adverse reactions associated with oral and parenteral use of cephalosporins: A retrospective population-based analysis.
abstract: BACKGROUND
  Few studies have provided population-based, route-specific data on allergy to cephalosporin or incidence of serious adverse drug reactions (ADRs).
  
  
  OBJECTIVE
  We investigated the incidence of new reports of cephalosporin-associated "allergy" and serious ADRs.
  
  
  METHODS
  We identified all members of the Kaiser Permanente Southern California health plan given cephalosporins (from January 1, 2010, through December 31, 2012), all new reports of cephalosporin-associated allergy, and all serious ADRs.
  
  
  RESULTS
  There were 622,456 health plan members exposed to 901,908 courses of oral cephalosporins and 326,867 members exposed to 487,630 courses of parenteral cephalosporins over the 3-year study period. New reports of allergy to cephalosporin were more frequent among women (0.56%; 95% CI, 0.54% to 0.57%) than among men (0.43%; 95% CI, 0.41% to 0.44%) per course (P < .0001). The most frequent serious cephalosporin-associated ADRs were Clostridium difficile infection within 90 days (0.91%), nephropathy within 30 days (0.15%), and all-cause death within 1 day (0.10%). None correlated with history of drug allergy. Physician-documented cephalosporin-associated anaphylaxis occurred with 5 oral exposures (95% CI, 1/1,428,571-1/96,154) and 8 parenteral exposures (95% CI, 1/200,000-1/35,971) (P = .0761). There were 3 documented cephalosporin-associated serious cutaneous adverse reactions (95% CI, 0-1 in 217,291). All were associated with the use of another antibiotic at the same time as cephalosporin.
  
  
  CONCLUSIONS
  Cephalosporins are widely and safely used, even in individuals with a history of penicillin allergy. Physician-documented cephalosporin-associated anaphylaxis and serious cutaneous adverse reactions are rare compared with C difficile infection within 90 days, nephropathy within 30 days, and all-cause death within 1 day.
authors.affiliation: Department of Allergy, Southern California Permanente Medical Group, San Diego Medical Center, San Diego, Calif. Electronic address: eric.m.macy@kp.org.
authors.forename: Eric
authors.initials: E
authors.lastname: Macy
authors.affiliation: Department of Research and Evaluation, Kaiser Permanente Health Care Program, Pasadena, Calif.
authors.forename: Richard
authors.initials: R
authors.lastname: Contreras
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D002140:California; D002511:Cephalosporins / Q000009:adverse effects*; D016360:Clostridioides difficile / Q000502:physiology; D004342:Drug Hypersensitivity / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D004761:Enterocolitis, Pseudomembranous / Q000139:chemically induced* / Q000382:microbiology / Q000503:physiopathology; D005260:Female; D006801:Humans; D007263:Infusions, Parenteral; D008297:Male; D008875:Middle Aged; D009393:Nephritis / Q000139:chemically induced* / Q000503:physiopathology; D012189:Retrospective Studies; D013221:State Health Plans
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins
keywords: Adverse drug reaction; Clostridium difficile; Stevens-Johnson syndrome; allergy; cephalosporin; death; hemolytic anemia; hospitalized; nephropathy; oral; outpatient; parenteral; serious cutaneous adverse reaction