Pharmacology: Amikacin is a semisynthetic aminoglycoside antibiotic derived from Kanamycin A. It has the advantage of not being inactivated by the same enzymes that render other aminoglycosides inactive against resistant organisms. It is active against some gram-positive and many gram-negative aerobic bacteria including Staph. aureus, E.coli, Ps. aeruginosa, Acenitobacter, Proteus spp. and Serratia.
Amikacin is rapidly and completely absorbed following IM administration. Peak plasma concentration is attained within 0.5 to 1.5 hours following IM administration and 15 to 30 minutes after end of IV infusion. The drug distributes to most extracellular fluid and does not cross the blood-brain barrier in therapeutically adequate concentrations in adults. Small improvement in penetration with inflamed meninges. Higher levels are achieved in the CSF of newborns than in adults. Most of the drug is excreted unchanged in urine with the elimination half-life of about 2 to 4 hours.
Amikacin crosses the placenta and small amounts appears in breast milk.