A fluoroquinolone (ciprofloxacin, levofloxacin, or moxifloxacin) may be considered an alternative agent for patients unable to tolerate ceftriaxone (or other third- or fourth-generation cephalosporins) (Class IIb; Level of Evidence C). 6. Ampicillin-sulbactam may be considered a treat- ment option for HACEK IE (Class IIb; Level of Evidence C). 7. Patients with HACEK IE who do not tolerate cef- triaxone therapy should be treated in consultation with an infectious diseases specialist (Class I; Level of Evidence C). Table 15. Therapy for Endocarditis Involving a Native or Prosthetic Valve or Other Prosthetic Material Resulting From Enterococcus Species Caused by Strains Resistant to Penicillin, Aminoglycosides, and Vancomycin Regimen Dose* and Route Duration, wk Strength of Recommendation Comments Linezolid 600 mg IV or orally every 12 h >6 Class IIb; Level of Evidence C Linezolid use may be associated with potentially severe bone marrow suppression, neuropathy, and numerous drug interactions. Patients with IE caused by these strains should be treated by a care team including specialists in infectious diseases, cardiology, cardiac surgery, clinical pharmacy, and, in children, pediatrics. Cardiac valve replacement may be necessary for cure. Or Daptomycin 10 12 mg/kg per dose >6 Class IIb; Level of Evidence C IE indicates infective endocarditis, and IV, intravenous. *Doses recommended are for patients with normal renal and hepatic function. Non-HACEK Gram-Negative Bacilli IE caused by non-HACEK Gram-negative aerobic bacilli (Enterobacteriaceae and Pseudomonas species) is rare. In that included 2761 patients seen in 61 hospitals in 28 countries, only 49 cases (1.8%) were attributable to non-HACEK Gram-negative aerobic bacilli. It is noteworthy that healthcare exposure was asso- ciated with the development of IE caused by this group of organisms in 57% of patients. 