In endodontic prophylaxis for a patient with a penicillin allergy, which antibiotic would be appropriate?

• A. Amoxicillin
• B. Doxycycline
• C. No antibiotic
• D. Clindamycin or azithromycin/clarithromycin depending on allergy

Answer: (D)

When someone is allergic to penicillin, you can’t give the penicillin-based prophylaxis used for dental procedures. Instead you pick an alternative that covers the same oral bacteria that could enter the bloodstream during endodontic work. The standard non-penicillin options are clindamycin or a macrolide such as azithromycin or clarithromycin. The exact choice depends on the patient’s specific allergy profile: if they can’t take macrolides, you’d use clindamycin; if they can’t take clindamycin, you’d use a macrolide. That’s why this option is the best: it reflects the appropriate non-penicillin alternatives for penicillin-allergic patients. Amoxicillin is wrong here because of the allergy, no antibiotic leaves a patient unprotected, and doxycycline can be considered in some contexts but is not the primary recommended choice in routine dental prophylaxis.