Once-daily or less frequent aminoglycoside dosing for empirical and directed therapy in neonates and children younger than 18 years

Aminoglycosides are hydrophilic drugs that are preferentially distributed into lean tissue, so fat-free mass is the most accurate weight descriptor for calculating aminoglycoside doses in childrenMoffett 2018. It is the consensus view of the Antibiotic Expert Group that for practicality, actual body weight can be used for dose calculations in children who are not obese. Children with obesity require individualised dosing (see Aminoglycoside use in children who are obese).

There are few data on aminoglycoside dosing in children and insufficient data to determine age-specific dosages. The recommended initial weight-based aminoglycoside dosing for empirical and directed therapy is shown in Initial aminoglycoside dosage for treating infection in children 1 month to younger than 18 years for children 1 month to younger than 18 years and Initial aminoglycoside dosage for treating infection in neonates for neonates. These dosages are based on the available data and the consensus view of the Antibiotic Expert Group. These dosages are not suitable for children with cystic fibrosis or for synergistic therapy (see Bartonella infections, Streptococcal endocarditis or Enterococcal endocarditis), resistant Mycobacterium avium complex infection, brucellosis or nocardiosis – seek expert advice.

Children with altered pharmacokinetics may require modified dosages – seek expert advice. Pharmacokinetic modelling studies indicate that gentamicin doses of up to 10 mg/kg may be required in critically ill children with augmented renal clearance¹ Avedissian 2020 Avedissian, 2021 Hartman 2020. However, the probability of toxicity is increased with higher dosages and there are currently no clinical data to support increased dosing in critically ill children. The standard initial empirical aminoglycoside dose is generally used in critically ill children, with early monitoring to inform further dosing – seek expert advice.

Note: Seek expert advice for the management of critically ill children with sepsis or septic shock.

If plasma concentration monitoring is indicated, see monitoring advice for children or neonates.

Table 1. Initial aminoglycoside dosage for treating infection in children 1 month to younger than 18 years
[NB1] [NB2] [NB3]
gentamicin or tobramycin amikacin
gentamicin or tobramycin in children 1 month to younger than 18 years
dose	7 mg/kg up to 560 mg [NB4] [NB5]
dosing frequency	24-hourly
maximum number of empirical doses [NB6]	3 doses (at 0, 24 and 48 hours)
amikacin in children 1 month to younger than 18 years
dose	20 mg/kg up to 1.5 g [NB4] [NB5]
dosing frequency	24-hourly
maximum number of empirical doses [NB6]	3 doses (at 0, 24 and 48 hours)
Note: NB1: There are few data on aminoglycoside dosing in children. The dosages recommended in this table are based on the available data and the consensus view of the Antibiotic Expert Group. NB2: Do not use the dosages in this table for children with cystic fibrosis or for synergistic therapy (see Bartonella infections, Streptococcal endocarditis or Enterococcal endocarditis), resistant Mycobacterium avium complex infection, brucellosis or nocardiosis – seek expert advice. NB3: In children with altered pharmacokinetics, the dosages in this table may not achieve the target area under the concentration–time curve. Consider monitoring the aminoglycoside plasma concentration from the first dose to optimise dosing. NB4: For obese children, use adjusted body weight to calculate the dose – see Aminoglycoside use in children with obesity. NB5: The maximum dose does not apply to children with septic shock or requiring intensive care support. NB6: For children with impaired kidney function (estimated glomerular filtration rate less than 50 mL/minute/1.73 m²), give a single dose, then seek expert advice for subsequent dosing or selection of an alternative antibiotic. Use the modified Schwartz formula to estimate glomerular filtration rate (GFR) in children older than 1 year – see the Glomerular filtration rate (GFR) calculator in children.

Table 2. Initial aminoglycoside dosage for treating infection in neonates
Crcek 2019

[NB1] [NB2] [NB3]
gentamicin or tobramycin amikacin
gentamicin or tobramycin
Gestational age at birth: younger than 30 weeks
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 14 days	5 mg/kg	48-hourly	2 doses (at 0 and 48 hours)
15 days or more	5 mg/kg	36-hourly	2 doses (at 0 and 36 hours)
Gestational age at birth: 30 to 34 weeks
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 10 days	5 mg/kg	36-hourly	2 doses (at 0 and 36 hours)
11 days or more	5 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
Gestational age at birth: 35 weeks or older
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 7 days	4 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
8 days or more	5 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
amikacin
Gestational age at birth: younger than 30 weeks
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 14 days	15 mg/kg	48-hourly	2 doses (at 0 and 48 hours)
15 days or more	15 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
Gestational age at birth: 30 to 34 weeks
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 10 days	15 mg/kg	36-hourly	2 doses (at 0 and 36 hours)
11 days or more	15 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
Gestational age at birth: 35 weeks or older
Postnatal age	Dose	Dosing frequency	Maximum number of empirical doses [NB4]
0 to 7 days	15 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
8 days or more	18 mg/kg	24-hourly	3 doses (at 0, 24 and 48 hours)
Note: NB1: There are few data on aminoglycoside dosing in neonates. The dosages recommended in this table are based on the available data and the consensus view of the Antibiotic Expert Group. NB2: Do not use the dosages in this table for neonates with cystic fibrosis or for synergistic therapy (eg for Bartonella infections, streptococcal endocarditis, or enterococcal endocarditis), resistant Mycobacterium avium complex infection, brucellosis or nocardiosis – seek expert advice. NB3: In neonates with altered pharmacokinetics, the dosages in this table may not achieve the target area under the concentration–time curve. Consider monitoring the aminoglycoside plasma concentration from the first dose to optimise dosing. NB4: For neonates with abnormal kidney function, give a single dose and seek expert advice for subsequent dosing or selection of an alternative antibiotic.

¹ Augmented renal clearance is a term used to describe the enhanced renal function seen in critically ill patients. The use of unadjusted doses of renally eliminated antimicrobials in these patients may result in treatment failureMahmoud 2017. Return