Extended interval aminoglycoside dose and dosing interval in adults by renal function

Creatinine clearance* (mL/min/70 kg)	Initial and maintenance dose^¶	Initial dosing interval
≥120	Use traditional intermittent dosing
40 to 119	Infuse over 1 hour: 7 mg/kg for gentamicin or tobramycin 15 mg/kg for amikacin	Determine by plotting serum concentration on nomogram
<40^Δ	Use traditional intermittent dosing

The maintenance dose and dosing intervals may need to be adjusted based on results of serum drug concentration monitoring. This is discussed in the topic review of aminoglycoside dosing, section on drug concentration monitoring. Extended interval aminoglycoside dosing is not recommended for particular indications and populations. As an example, the doses listed in this table do NOT apply to aminoglycosides being used as synergistic therapy for gram positive infections or aminoglycoside use in cystic fibrosis or pregnant patients. Such exclusions are discussed in more detail in the topic on aminoglycoside dosing.

* Creatinine clearance may be estimated by use of Cockroft-Gault equation. Calculators for estimation of creatinine clearance are available in UpToDate.

¶ The appropriate dosing weight to use for dose calculation is discussed in the topic on aminoglycoside dosing.

Δ Some institutions use a lower threshold of 20 to 30 mL/min for using traditional intermittent instead of extended interval dosing. In such cases, for patients who have a creatinine clearance between this lower limit and 40 mL/min, the calculated aminoglycoside dose is administered at a 48-hour interval.

Graphic 50722 Version 9.0