Family Nurse Practitioner Exam

For a patient with a severe penicillin allergy, which antibiotic is the safest choice for treating strep throat?

1. Cephalexin (Keflex)

2. Azithromycin (Zithromax)

3. Cefuroxime axetil (Ceftin)

4. Levofloxacin (Levaquin)

The correct answer is: Azithromycin (Zithromax)

When treating a patient with a severe penicillin allergy for strep throat, azithromycin is the safest choice due to its different structural composition and mechanism of action compared to penicillin. Azithromycin belongs to the macrolide class of antibiotics, which does not cross-react with penicillin, making it a suitable alternative for patients with penicillin allergies. This class of antibiotics is effective against the bacteria responsible for strep throat (Streptococcus pyogenes) and offers a safe treatment option without the risk of allergic reactions commonly associated with penicillin or penicillin-related drugs. Cephalexin and cefuroxime axetil are both cephalosporins, which, while effective against strep bacteria, have a structural similarity to penicillin and may trigger an allergic response in individuals sensitive to penicillin. Levofloxacin, a fluoroquinolone, is generally not the first-line treatment for strep throat due to its broader spectrum and potential side effects, making azithromycin the most appropriate and safest choice in this scenario.