Amikacin agents/therapy

Gentamicin and tobramycin are equally effective. Tobramycin has slightly better MICs to Pseudomonas. Amikacin generally is reserved for multi-drug resistant bacteria. Typically used as a short course of therapy followed by a switch to an oral agent. 

Penicillin plus streptomycin is effective for enterococcal endocarditis and 2-week therapy of viridans streptococcal endocarditis. Gentamicin has largely replaced streptomycin for these indications. Streptomycin remains a useful agent for treating enterococcal infections, however, because approximately 15% of enterococcal isolates that are resistant to gentamicin (and therefore to netilmicin, tobramycin, and amikacin) will be susceptible to streptomycin. 

Cometta A, Calandra T, Gaya H, et al. Monotherapy with meropenem versus combination therapy with ceftazidime plus amikacin as empirical therapy for fever in granulocytopenic patients with cancer. Antimicrob Agents Chemother 1996 40 1108-1115. 

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