A nurse is caring for a client diagnosed with streptococcal pharyngitis who has a documented allergy to penicillin. Which antibiotic is most appropriate to prescribe for this patient?

• A. Erythromycin
• B. Cephalexin
• C. Amoxicillin
• D. Vancomycin

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the condition - Streptococcal pharyngitis is a bacterial infection caused by Streptococcus pyogenes. It is commonly treated with antibiotics to eliminate the bacteria and prevent complications.
2. Step 2: Identify the contraindication - The patient has a documented allergy to penicillin, which rules out penicillin-based antibiotics such as Amoxicillin and Cephalexin (a cephalosporin that can cross-react with penicillin in allergic individuals).
3. Step 3: Evaluate alternative antibiotics - Erythromycin is a macrolide antibiotic that is often used as an alternative for patients allergic to penicillin. It is effective against Streptococcus pyogenes.
4. Step 4: Consider Vancomycin - Vancomycin is typically reserved for severe infections or resistant strains of bacteria. It is not the first-line treatment for streptococcal pharyngitis unless other options are ineffective or contraindicated.
5. Step 5: Select the most appropriate antibiotic - Based on the patient's allergy and the effectiveness of the antibiotics listed, Erythromycin is the most appropriate choice for treating streptococcal pharyngitis in this case.