For strep pharyngitis in a penicillin-allergic patient, which antibiotic is a common alternative?

For strep pharyngitis in a penicillin-allergic patient, which antibiotic is a common alternative?

• A. Amoxicillin
• B. Cefdinir
• C. Erythromycin
• D. Penicillin G

Answer: (C)

When penicillin cannot be used, you need an antibiotic that reliably treats Streptococcus pyogenes without triggering a penicillin-type reaction. Erythromycin fits that role well because it’s a macrolide with proven activity against group A strep and does not share a beta-lactam structure, so it avoids cross-reactivity in penicillin-allergic patients. Amoxicillin and penicillin G are penicillin-type antibiotics and are avoided in someone with a penicillin allergy. Cefdinir is a cephalosporin; while some penicillin-allergic patients can tolerate certain cephalosporins, macrolides remain the classic and commonly used alternative for strep pharyngitis in this scenario.

When penicillin cannot be used, you need an antibiotic that reliably treats Streptococcus pyogenes without triggering a penicillin-type reaction. Erythromycin fits that role well because it’s a macrolide with proven activity against group A strep and does not share a beta-lactam structure, so it avoids cross-reactivity in penicillin-allergic patients. Amoxicillin and penicillin G are penicillin-type antibiotics and are avoided in someone with a penicillin allergy. Cefdinir is a cephalosporin; while some penicillin-allergic patients can tolerate certain cephalosporins, macrolides remain the classic and commonly used alternative for strep pharyngitis in this scenario.