Which of the following drugs is most effective against an organism producing aminoglycoside inactivating enzymes?: (A) Amikacin, (B) Streptomycin, (C) Gentamicin, (D) Tobramycin
Answer is A. (Ref: KDT 6/e p724) Amikacin is most resistant to aminoglycoside inactivating enzymes. Aminoglycosides are not effective against anaerobes.