What Alternative to Penicillin in the Allergic Patient?

Advances in environmental sanitation, immunizations, antimicrobial therapy, and medical research have greatly reduced the impact of infectious diseases (IDs) on our communities. Nonetheless, infections and the cost of treating them remain a burden to the health care system.

In primary care practice, we may spend more time making referrals for suspected ID than actually treating infected patients. Here, as a brush up, is the sixth in our series of 10 practical ID pearls. 

6. Can imipenem/cilastatin be used to treat a patient who is allergic to penicillin?

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Then click here for the answer and discussion.

Answer: Imipenem /cilastatin, a broad-spectrum carbapenem, can be used relatively safely in patients who are allergic to penicillin.

Early studies reported cross-reactivity of penicillin with imipenem/cilastatin to be approximately 47%.¹ More recent studies report a cross-reactivity rate of less than 1% to 5%.²  In those who have had a mild reaction to penicillin, imipenem has demonstrated relative safety. However, if a patient has experienced an anaphylactic reaction to penicillin, then imipenem or carbapenem-related drugs should be used with caution or avoided if another antibiotic can be substituted.

References:
1. Prescott W, DePestel D, Ellis J, Regal R. Incidence of carbapenem-associated allergic-type reactions among patients with versus patients without a reported penicillin allergy. Clin Infect Dis. 2004;38:1102-1107.
2. Scheetz M, Bolon M, Esterly J, et al. Life-years gained with meropenem over ciprofloxacin in penicillin-allergic patients with gram-negative bacilli sepsis: results of probabilistic model. Pharmacotherapy. 2013;31:469-479.

Click below for:

Practical ID Pearl #1

Pracitcal ID Pearl #2

Pracitcal ID Pearl #3

Pracitcal ID Pearl #4

Pracitcal ID Pearl #5