Which antibiotic is NOT typically used in the empiric treatment of infective endocarditis?

In the context of empiric treatment for infective endocarditis, the primary goal is to cover the most common organisms known to cause this condition, which typically include Staphylococcus aureus, Streptococcus viridans, and enterococci.

Vancomycin is commonly used because it provides adequate coverage for methicillin-resistant Staphylococcus aureus (MRSA) and other resistant Gram-positive organisms. Gentamicin may also be used in combination with a beta-lactam antibiotic for synergy, particularly in cases involving enterococci or certain strains of viridans group streptococci. Amoxicillin is utilized for its effectiveness against Streptococcus viridans and, in certain circumstances, for enterococci.

Ciprofloxacin, however, is a fluoroquinolone that primarily provides coverage for Gram-negative organisms and has limited activity against the typical pathogens associated with infective endocarditis. Its spectrum of activity does not adequately address the Gram-positive cocci that are the predominant etiological agents in this condition, making it unsuitable for the empiric treatment of infective endocarditis. Thus, it is the antibiotic that is not typically included in the initial empiric therapy regimen.