Palmetto Health Children’s Hospital
EXTENDED DOSE AMINOGLYCOSIDE THERAPY
Definition & Rationale:
Extended dose (ED) aminoglycoside therapy involves giving the total daily dose as one single dose rather
than divided doses. ED aminoglycoside therapy takes advantage of the relatively long post antibiotic effect
and concentration dependent bactericidal activity of aminoglycoside antibiotics.
Advantages:
1) Equal or greater efficacy through higher serum and tissue concentrations.
2) No increase in renal toxicity because uptake and accumulation of drug in renal cortex is a saturable
process. Even at higher doses there is no increase in uptake by renal cells.
3) More cost effective because of:
a) Reduction in numbers of levels drawn
b) Reduction in pharmacy and nursing time
Exclusions:
1) < 6 months of age
2) Significant Burns
3) Meningitis
4) Part of synergistic combination (i.e. for endocarditis)
5) Severe renal dysfunction with or without dialysis
Dosing: (using adjusted body weight for morbidly obese patients)
4 mg/kg
7 mg/kg
10 mg/kg
Uncomplicated UTIs
All other systemic infections
Cystic Fibrosis
*Neofax® extended dosing of aminoglycoside therapy in neonates does not apply to above guidelines
Monitoring:
1) Obtain random level 6-14 hours after first dose or dose change (10 hours is recommended)
2) Plot on nomogram (see nomogram below)
3) If level falls in the area designated q24h, q36h, or q48h, then dosing interval should be every 24, 36, 48
hours respectively. If it is on the line, choose the longer interval.
4) If level is above the nomogram, the scheduled doses, if any, should be held and serial levels followed to
determine timing of the next dose
5) If the level is less than 2 mcg/ml, the dosing interval should be every 24 hours. However, if the level is
less than 0.2 mcg/ml, dosing should change to traditional dosing.
6) If length of therapy is greater than 5 days, obtain a random level weekly.
7) In obese patients, patients with altered volume of distribution (i.e. edema), or patients who are not
responding to antibiotic therapy, monitoring a peak will help determine the dose needed for maximal
response.
a) Peak should be drawn at the end of one hour infusion.
b) A clinical response of 90% is achieved when the serum peak concentration is 8-10 times the
MIC of the organism.
Rev. 04/2009
Rev. 04/2009