What is the adult prophylaxis premedication for a patient without a penicillin allergy prior to a dental appointment?

• A. Clindamycin 600 mg
• B. Amoxicillin 2 g 1 hour before
• C. Azithromycin 500 mg
• D. Cephalexin 2 g

Answer: (B)

When giving antibiotic prophylaxis to adults who have no penicillin allergy, the preferred choice is amoxicillin 2 g taken orally about one hour before the dental procedure. Amoxicillin is chosen because of its strong oral bioavailability and reliable blood and tissue concentrations that help prevent bacteremia during dental work, particularly against streptococci implicated in endocarditis. The timing of about one hour before the procedure ensures the drug is at effective levels when the procedure begins (guidelines generally recommend a 30–60 minute window). Alternatives like clindamycin, azithromycin, or cephalexin are reserved for those with a penicillin allergy or intolerance; they are not first-line in patients without allergy.