Which antibiotic is recommended for IV administration for patients with SBE prophylaxis who are allergic to penicillin?

Cefazolin is the recommended antibiotic for intravenous administration in patients requiring endocarditis prophylaxis when they are allergic to penicillin. This is largely due to its effectiveness in providing coverage against the bacteria that commonly cause infective endocarditis. Cefazolin belongs to the first-generation cephalosporin class and, despite having a chemical structure that is related to penicillin, it is generally considered safe for individuals with a penicillin allergy, particularly for those patients who might experience anaphylaxis with penicillin.

In the case of patients who cannot tolerate penicillin, cefazolin serves as a viable alternative because it has a similar spectrum of activity and can be trusted to effectively minimize the risk of bacterial endocarditis during procedures that could introduce bacteria into the bloodstream, such as dental work. Thus, its use is well-grounded in clinical guidelines.

The other options do not fit the same criteria for endocarditis prophylaxis. Amoxicillin is often used for prophylaxis but is not suitable for patients with a penicillin allergy. Ciprofloxacin and gentamicin, while they may play roles in treating certain infections, are not typically used for this specific prophylactic indication in the context of endocarditis.