Amikacin

Indications

Amikacin is used for: Tuberculosis, Complicated and recurrent urinary tract infections, Severe Gram-negative infections, Non-tubercular mycobacterial infections, Bacterial septicemia, Infections of the respiratory tract, Bones and joints, Central nervous system and skin and soft tissue, Intra-abdominal infections, Burns, Postoperative infections, Meningitis, Peritonitis, Neonatal sepsis

Adult Dose

Parenteral Uncomplicated urinary tract infections Adult: 250 mg bid, given via IM, IV inj over 2-3 minutes or as IV infusion. Severe Gram-negative infections resistant to gentamicin and tobramycin Adult: 15 mg/kg daily in equally divided doses injected every 8 or 12 hr for 7-10 days. Max: Up to 500 mg every 8 hr in life-threatening infections. Max cumulative dose: 15 g. Doses may be given via IM, slow IV inj over 2-3 minutes or IV infusion. Hospital Acquired Pneumonia 20 mg/kg/day IV; may administer with antipseudomonal beta-lactam or carbapenem

Child Dose

Parenteral Child: IV, IM 15–22.5 mg/kg/day q8h Neonates Aged <7 days <29 weeks gestational age: 18 mg/kg IV/IM q48hr 30-33 weeks gestational age: 18 mg/kg IV/IM q36hr >34 weeks gestational age: 15 mg/kg IV/IM q24hr Aged >7 days 30-33 weeks gestational age: 15 mg/kg IV/IM q24hr >34 weeks gestational age: 15 mg/kg IV/IM q12-18hr Aged 8-28 days old & <29 weeks gestational age 15 mg/kg IV/IM q36hr Neonates Aged >28 days old & <29 weeks gestational age 15 mg/kg IV/IM q24hr Also use this dose for the following: significant asphyxia, indomethacin for PDA, poor cardiac output, or renal impairment

Renal Dose

Renal impairment: Doses should be adjusted either by administering normal doses at prolonged intervals or by administering reduced doses at fixed intervals based on the patient's CrCl or serum creatinine values. Simple doses schedule for renal impairment is given below: Renal function Dosage schedule Mild impairment 500 mg every 18 hours Moderate impairment 500 mg every 24 hours Severe impairment 250 mg every 24 hours. or CrCl >90 mL/min and aged <60 yr: q8hr CrCl 60-90 mL/min OR aged ?60 yr: q12hr CrCl 25-60 mL/min: q24hr CrCl 10-25 mL/min: q48hr CrCl <10 mL/min: q72hr Administer after dialysis in ESRD

Administration

IV/IM Administration IM: Administer undiluted to upper outer quadrant of buttocks IV: Infuse over 30-60 min in adults and children; infuse over 1-2 hr in infants Reconstitution: IV infusion: For adults, add 500 mg of amikacin to 100-200 mL of compatible IV fluid (e.g. NaCl 0.9%, dextrose 5%). For pediatric patients, the vol of diluent depends on the prescribed dosage.

Contra Indications

Pregnancy, perforated ear drum, myasthenia gravis, hypersensitivity.

Precautions

Renal impairment; vertigo, tinnitus. Discontinue if signs of ototoxicity, neurotoxicity or hypersensitivity occurs; lactation. Safety has not been established for treatment period >14 days. Monitor renal function before and during treatment. Lactation: excretion in milk unknown/not recommended

Pregnancy-Lactation

Pregnancy Category: D Lactation: excretion in milk unknown/not recommended

Interactions

Amphotericin B may lead to increased nephrotoxicity and reduced clearance of amikacin when used together. Potentially Fatal: Increased ototoxic or nephrotoxic effects with other nephrotoxic or ototoxic drugs. Enhanced neuromuscular blockade with neuromuscular blocking drugs. Increased risk of ototoxicity with potent diuretics.

Adverse Effects

Side effects of Amikacin : 1-10% Neurotoxicity, Nephrotoxicity (if trough >10 mg/L), Ototoxicity <1% Hypotension, Headache, Drug fever, Rash, Nausea, Vomiting, Eosinophilia, Paresthesia, Tremor, Arthralgia, Weakness, Allergic reaction Potentially Fatal: Ototoxicity, nephrotoxicity, neuromuscular blockade.

Mechanism of Action

Amikacin binds to 30S ribosomal subunits of susceptible bacteria, thus inhibiting its protein synthesis.