Gentamicin Dosing Calculator
Compute once-daily (7 mg/kg Hartford) and traditional (1.7 mg/kg q8h) gentamicin doses from actual weight, CrCl, and clinical indication — with peak/trough monitoring targets.
Use the Gentamicin Dosing Calculator
Patient Parameters
Educational reference only. All dosing results must be verified by a licensed pharmacist or physician before administration. This tool does not replace clinical judgment or therapeutic drug monitoring.
Enter patient data and click Calculate Dose
Patient Pharmacokinetic Estimates
Once-Daily Dosing — Hartford Nomogram
7 mg/kg × dosing weight; interval selected by CrCl. Obtain 6–14 h post-dose level to confirm interval.
Traditional Multiple-Daily Dosing
Illustrative indication-specific starting doses; endocarditis synergy uses 1 mg/kg in this model. Specialist dosing and drug-level monitoring are required.
Monitoring Targets — —
Summary
This calculator provides gentamicin initial dosing for two strategies: once-daily (extended-interval, Hartford nomogram) and traditional multiple-daily dosing. It estimates creatinine clearance via Cockcroft-Gault, adjusts dosing weight for obesity, and displays indication-specific peak and trough monitoring targets for UTI, sepsis/bacteremia, endocarditis synergy, and cystic fibrosis/bronchiectasis. All results are for educational and clinical-support reference only; a licensed pharmacist or physician must verify dosing before administration.
How it works
- Enter patient age, sex, height, and actual body weight.
- Enter the serum creatinine to estimate creatinine clearance (Cockcroft-Gault).
- Select the clinical indication to display appropriate peak and trough targets.
- The calculator determines dosing weight — actual body weight (ABW) if not obese, or adjusted body weight (DW) if ABW > 1.3 × IBW.
- Once-daily dose is computed at 7 mg/kg dosing weight; interval (q24h / q36h / q48h) is selected by CrCl using Hartford nomogram criteria.
- Traditional dose is computed at 1.7 mg/kg (or 2 mg/kg for severe infections) per interval, with the interval lengthened for reduced CrCl.
- Dose recommendations and peak/trough targets are shown side by side for clinical decision support.
Use cases
- Calculate an initial once-daily gentamicin dose for gram-negative bacteremia.
- Determine traditional q8h/q12h gentamicin dosing for a patient with mild renal impairment.
- Look up indication-specific peak and trough targets before ordering monitoring levels.
- Estimate CrCl from a bedside serum creatinine before selecting the dosing interval.
- Support pharmacy students learning gentamicin pharmacokinetics and monitoring.
- Cross-check a clinical dose recommendation during infectious disease rounds.
- Assess dose adjustment needed for a renally impaired critically ill patient.
- Review Hartford nomogram interval selection criteria at the point of care.