drug allergy

If a person is allergic to penicillin (red itchy rash), can Rocephin safely be taken?

Is there an allergy test that can be done?

[Jennifer R, RPh]

Ceftriaxone should be used cautiously in patients with hypersensitivity to penicillin. The structural similarity between ceftriaxone and penicillin means that cross-reactivity can occur. Penicillins can cause a variety of hypersensitivity reactions ranging from mild rash to fatal anaphylaxis. Patients who have experienced severe penicillin hypersensitivity should not receive ceftriaxone. The incidence of cross-sensitivity is difficult to determine since the incidence varies depending on the cephalosporin involved and the type of reaction being considered. Cefazolin induced an allergic reaction in 4% of patients known to have a penicillin allergy.

Jennifer R RPh www.drugstore.com