Start after 3 sets of blood cultures are obtained (if possible)
Therapy should be based on:
Whether the patient has received prior antibiotic therapy
Prosthetic valves
Local antibiotic resistance patterns or knowledge of prior<unk>  cultures
Prior hospitalizations and risk of MRSA
Options:
Ampicillin/Sulbactam 12g/day IV in 4 doses + Gentamicin 3mg/kg/day IV in 2 or 3 doses
Amoxicillin/Clavulanate 12g/day in 4 dose + Gentamicin 3mg/kg/day IV in 2 or 3 doses
Oxacillin or Nafcillin 2g IV six times daily + Gentamicin 1mg/kg IV three times daily AND Ampicillin 2g IV six times daily
Daptomycin 6mg/kg IV once daily
Suspected MRSA:
Vancomycin 30mg/kg/day IV in 2 doses PLUS
Gentamicin 3mg/kg/day IV in 2 or 3 doses PLUS
Ciprofloxacin 1000mg/day PO in 2 doses or 800 mg/day IV in 2 doses
Vancomycin 30mg/kg/day IV in 2 doses PLUS
Gentamicin 3mg/kg/day IV in 2 or 3 doses PLUS
Rifampin 1200 mg/day PO in 2 doses
Vancomycin 15-20 mg/kg IV BID daily
Daptomycin 6mg/kg IV once daily
Same as native valve<unk>  empiric therapy
All antibiotics options are given as a single dose 1 hour prior to the dental procedure
Options:
Amoxicillin 2g or 50mg/kg
Ampicillin 2g (50mg/kg) IV or IM
Cefazolin or Ceftriaxone 1g (50mg/kg) IM or IV
Clindamycin 600mg (20mg/kg) PO or IV
Azithromycin or Clarithromycin 500mg (15mg/kg) PO
Endocarditis
Critical
Myocarditis
Sepsis
Myocarditis 
PNA with respiratory failure
Constrictive pericarditis
Peritonitis