Gentamicin in Renal Replacement Therapy
Dosing in Outpatient Intermittent HDF
Loading dose – 2.5 mg/kg up to a maximum of 180 mg.
Average doses based on weight :
Weight (kg) | Dose (mg) |
---|---|
<60 | 80-120 |
60.1 - 80 | 160 - 180 |
>80 | 180 |
Maintenance dose – should be based on the pre dialysis serum concentration. If pre HDF levels are < 2.5 mg/l give a further dose at the end of HDF calculated at 2mg/kg body weight
Average dose calculations based on weight:
Weight (kg) | Dose (mg) |
---|---|
<60 | 80 - 120 |
60.1 - 80 | 120 - 160 |
>80 | 160 - 180 |
Rationale: Serum levels are monitored closely due to the narrow therapeutic window of Gentamicin. Ideal trough levels are < 2mg/l and peak levels 6-12 mg/l. Although nephrotoxicity is of little concern in patients with ESRD ototoxicity is still a significant concern. Less than 50% of Gnetamicin is removed in a single 4 hour HD session. Therefore further dosing when predialysis levels (which correlate to trough levels) drop to < 2.5 mg/l is advised to maintain ideal trough levels.
Dosing in Patients Receiving Acute HD/ HDF (daily, every other day , > 3 /week)
Loading dose – 2.5 mg/kg up to a maximum of 180 mg. As in intermittent HD.
Maintenance dose – same as in intermittent HD (as above).
However for inpatients we advise that a further level is taken 30 mins after HD to ensure peak concentration of 6-12 mg/l. If the peak level is less than the above range then give a further dose calculated at 2mg/kg.
References
- GGC Gentamicin guideline for patients on haemodialysis 2014 and suggested revisions–Whittle M., Thomson P.,Thomson A.
- Florczykowski B. Et. Al. Gentamicin Dosing and Monitoring Challenges in End Stage Renal Failure. Advances in Pharmacoepidemiology and Drug Safety 2013;2:1-3 [pdf]
- Kevin M. Influence of Haemodialysis on Gentamicin pharmokinetics, removal during haemodialysis and recommended dosing. Clinical Journal of American Society of Nephrology 2008;3(2):355-361
- Guisado-Gil A.B. et al. Gentamicin as empirical treatment in haemodialysis patients: safety, pharmacokinetics and pharmacodynamics. Therapeutic Apheresis and Dialysis 2019;23: 550-555
Content by Dr Nadeeka Rathnamalala and the Renal Team