Besides clindamycin, which antibiotic may be used for penicillin-allergic patients in odontogenic infections?

• A. Azithromycin
• B. Amoxicillin
• C. Doxycycline
• D. Ciprofloxacin

Answer: (A)

When penicillin cannot be used, you still want an antibiotic that covers the usual oral pathogens—streptococci and oral anaerobes. Azithromycin, a macrolide, fits this role well. It has good activity against many gram-positive cocci and some anaerobes commonly found in odontogenic infections, plus excellent oral bioavailability and tissue penetration. Its convenient dosing aids adherence, which is helpful in dental infections treated on an outpatient basis.

Doxycycline can be used in some penicillin-allergic cases, but it has drawbacks in dental infections (age/pregnancy considerations and broader resistance concerns). Amoxicillin is a penicillin-class drug, so it isn’t suitable for someone with a penicillin allergy. Ciprofloxacin provides limited coverage of the anaerobes important in dental infections and isn’t considered a first-line choice here.

Thus azithromycin is the best match among the options for penicillin-allergic patients with odontogenic infections.