Version July 2025
| American Heart Association (AHA) | European Society of Cardiology (ESC) (MIC ≤0.125 mcg/mL) | |
| Adult (MIC ≤0.12 mcg/mL) | Pediatric (MIC ≤0.1 mcg/mL) | |
| 4-week regimens¶: | 4-week regimens: | 4-week regimensΔ: |
| Aqueous penicillin G 12 to 18 million units per 24 hours IV either continuously or in 4 or 6 divided doses or (if penicillin is unavailable) Ampicillin 2 g IV every 4 hours or Ceftriaxone 2 g per 24 hours IV or IM in 1 dose | Aqueous penicillin G 200,000 to 300,000 units/kg per 24 hours IV in 6 divided doses (maximum dose: 24 million units per 24 hours) or (if penicillin is unavailable) Ampicillin 200 to 300 mg/kg per 24 hours IV divided in 4 or 6 divided doses (maximum dose: 12 g per 24 hours) or Ceftriaxone 100 mg/kg per 24 hours IV§ in 2 divided doses or 80 mg/kg in 1 daily dose (maximum dose: 4 g per 24 hours; if dose is >2 g per 24 hours, use divided dosing every 12 hours) | Aqueous penicillin G¶ 12 to 18 million units per 24 hours IV in 4 or 6 divided doses or continuous infusion or Amoxicillin 100 to 200 mg/kg per 24 hours IV in 4 to 6 divided doses or Ceftriaxone¶¥ 2 g per 24 hours IV or IM in 1 dose |
| Beta-lactam-intolerant patients: Vancomycin◊ 30 mg/kg per 24 hours IV in 2 divided doses | Beta-lactam-intolerant patients: Vancomycin◊ 40 mg/kg per 24 hours IV in 2 or 3 divided doses (maximum dose: 2 g per 24 hours) | Beta-lactam-intolerant patients: Vancomycin◊ 30 mg/kg per 24 hours IV in 2 divided doses |
| 2-week regimens‡: | 2-week regimens‡: | 2-week regimensΔ‡: |
| Either Aqueous penicillin G 12 to 18 million units per 24 hours IV either continuously or in 6 divided doses or Ceftriaxone 2 g per 24 hours IV or IM in 1 dose plus Gentamicin†,** 3 mg/kg per 24 hours IV or IM in 1 dose (preferred) or in 3 divided doses | Not recommended for children due to lack of data | Either Aqueous penicillin G 12 to 18 million units per 24 hours IV in 4 to 6 divided doses or continuous infusion or Amoxicillin 100 to 200 mg/kg per 24 hours IV in 4 to 6 divided doses or Ceftriaxone¶¥ 2 g per 24 hours IV or IM in 1 dose plus Gentamicin†,¶¶ 3 mg/kg per 24 hours IV or IM in 1 dose |
The doses above are intended for patients with normal kidney function. The doses of many of these agents must be adjusted in the setting of kidney function impairment; refer to the individual drug monographs included within UpToDate for renal dosing adjustments.
Wherever intramuscular administration is provided as an alternative, intravenous route is preferred, particularly in infants and children.IM: intramuscularly; IV: intravenously; MIC: minimum inhibitory concentration.
* MIC thresholds differ between guidelines. AHA adult guidelines use MIC ≤0.12 mcg/mL; AHA pediatric guidelines use MIC ≤0.1 mcg/mL. ESC guidelines use MIC ≤0.125 mcg/mL.
¶ Preferred in most patients >65 years or with impairment of 8th nerve or kidney function.
Δ Pediatric doses (should not exceed adult doses): Penicillin G 200,000 units/kg per 24 hours IV in 4 to 6 divided doses; amoxicillin 300 mg/kg per 24 hours IV in 4 to 6 divided doses; ceftriaxone 100 mg/kg per dose IV or IM daily; vancomycin 40 mg/kg per 24 hours IV in 2 or 3 divided doses; gentamicin 3 mg/kg per 24 hours IV or IM in a single daily dose or in 3 divided doses.
◊ Vancomycin therapy only recommended for patients allergic to penicillin and cephalosporins; vancomycin dose adjusted for trough concentration of 10 to 15 mcg/mL. Penicillin desensitization can be attempted in stable patients.
§ In infants and children, intravenous antibiotics are recommended rather than intramuscular agents.
¥ Preferred for outpatient therapy.
‡ For noncomplicated infective endocarditis. Not intended for patients with known cardiac or extracardiac abscess or for creatinine clearance <20 mL/min, impaired 8th nerve function, or infection due to Abiotrophia, Granulicatella spp, or Gemella spp.
† Kidney function and gentamicin serum concentrations should be monitored at least once per week. Gentamicin dose adjusted for peak serum concentrations 3 to 4 mcg/mL, trough <1 mcg/mL when 2 to 3 divided doses used; when given in a single daily dose, pre-dose (trough) concentrations should be <1 mcg/mL. Per ESC guidelines, post-dose (peak, 1 hour after injection) serum concentrations should be approximately 10 to 12 mcg/mL (per AHA guidelines, there is no role for measuring peak gentamicin concentration following single daily dosing).
** Gentamicin may be given as a single daily dose (3 mg/kg per day; preferred in outpatients) or in 2 to 3 equally divided doses (adjusted to achieve a peak serum level of 3 to 4 mcg/mL; preferred in hospitalized patients when serum concentrations can be followed).
¶¶ Netilmicin (4 to 5 mg/kg/day IV in 1 dose) is an alternative.