Tolerability of aztreonam and carbapenems in patients with IgE-mediated hypersensitivity to penicillins

J Allergy Clin Immunol. 2015 Apr;135(4):972-976. doi: 10.1016/j.jaci.2014.10.011. Epub 2014 Nov 22.


Background: Studies performed on samples larger than 100 subjects with a documented IgE-mediated hypersensitivity to penicillins have demonstrated a cross-reactivity rate of approximately 1% between penicillins and both imipenem and meropenem, whereas a single study found a cross-reactivity rate of 6.2% with aztreonam in 16 such subjects.

Objective: To assess the cross-reactivity and tolerability of aztreonam and 3 carbapenems (imipenem-cilastatin, meropenem, and ertapenem) in patients with documented IgE-mediated hypersensitivity to penicillins.

Methods: A total of 212 consecutive subjects with immediate reactions to penicillins and positive results on skin tests to at least 1 penicillin reagent underwent skin tests with aztreonam and carbapenems; subjects with negative results were challenged with escalating doses of aztreonam and carbapenems.

Results: All subjects displayed negative skin test results to both aztreonam and carbapenems; 211 accepted challenges and tolerated them. Challenges were not followed by full therapeutic courses.

Conclusions: These data indicate the tolerability of both aztreonam and carbapenems in penicillin-allergic subjects. In those who especially require these alternative β-lactams, however, we recommend pretreatment skin tests, both because rare cases of cross-reactivity have been reported and because negative results indicate tolerability.

Keywords: Aztreonam; cross-reactivity; ertapenem; imipenem; meropenem; penicillin allergy; skin tests; tolerability.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Aztreonam / adverse effects*
  • Aztreonam / chemistry
  • Carbapenems / adverse effects*
  • Carbapenems / chemistry
  • Cross Reactions
  • Drug Hypersensitivity / epidemiology
  • Drug Hypersensitivity / immunology*
  • Drug Substitution
  • Female
  • Humans
  • Hypersensitivity, Immediate / epidemiology
  • Hypersensitivity, Immediate / immunology*
  • Immune Tolerance*
  • Male
  • Middle Aged
  • Penicillins / adverse effects*
  • Penicillins / chemistry
  • Skin Tests
  • Young Adult


  • Carbapenems
  • Penicillins
  • Aztreonam