Therapy of NVE Caused by Highly Penicillin-Susceptible VGS and Streptococcus gallolyticus (bovis) Regimen Dose* and Route Duration, wk Strength of Recommendation Comments Aqueous crystalline penicillin G sodium 12 18 million U/24 h IV either continuously or in 4 or 6 equally divided doses 4 Class IIa; Level of Evidence B Preferred in most patients >65 y or patients with impairment of eighth cranial nerve function or renal function. Ampicillin 2 g IV every 4 h is a reasonable alternative to penicillin if a penicillin shortage exists. Or Ceftriaxone sodium 2 g/24 h IV/IM in 1 dose 4 Class IIa; Level of Evidence B Aqueous crystalline penicillin G sodium 12 18 million U/24 h IV either continuously or in 6 equally divided doses 2 Class IIa; Level of Evidence B 2-wk regimen not intended for patients with known cardiac or extracardiac abscess or for those with creatinine clearance of <20 mL/min, impaired eighth cranial nerve function, or Abiotrophia, Granulicatella, or Gemella spp infection; gentamicin dose should be adjusted to achieve peak serum concentration of 3 4 g/mL and trough serum concentration of <1 g/mL when 3 divided doses are used; there are no optimal drug concentrations for single daily dosing. Or Ceftriaxone sodium 2 g/24 h IV or IM in 1 dose 2 Class IIa; Level of Evidence B Plus Gentamicin sulfate 3 mg/kg per 24 h IV or IM in 1 dose 2 Vancomycin hydrochloride 30 mg/kg per 24 h IV in 2 equally divided doses 4 Class IIa; Level of Evidence B Vancomycin therapy is reasonable only for patients unable to tolerate penicillin or ceftriaxone; vancomycin dose should be adjusted to a trough concentration range of 10 15 g/mL. IM indicates intramuscular; IV, intravenous; NVE, native valve infective endocarditis; and VGS, viridans group streptococci. 