Amikacin dose
Reading File
Finding Sources
Searching the Web
amikacin dosing guidelines 2025 adult renal adjustment
Reading File
Reading File
Here is a comprehensive summary of Amikacin dosing:
Amikacin Dosing
Standard Adult Dosing
| Indication | Dose | Frequency |
|---|---|---|
| Serious infections (systemic) | 15 mg/kg/day | Once daily (OD) preferred |
| Traditional divided dosing | 7.5 mg/kg | Every 12 h |
| Traditional divided dosing | 5 mg/kg | Every 8 h |
| Maximum daily dose | 1.5 g/day | — |
| UTI (uncomplicated, single dose) | 15 mg/kg × 1 | Single dose |
| Non-TB mycobacteria | 15–20 mg/kg | 3× weekly |
| TB (second-line) | 15 mg/kg | OD or 5×/week IM |
Preferred strategy: Extended-interval (once-daily) dosing — higher peak concentrations exploit concentration-dependent killing and the postantibiotic effect, with improved efficacy and less toxicity compared to divided dosing.
Pediatric Dosing
- 15–22.5 mg/kg/day in divided doses every 8 hours (7.5 mg/kg q8h)
- Neonates: 7.5 mg/kg every 12 h (or every 18–24 h in preterm/low birth weight)
Pharmacokinetic Targets (TDM)
| Parameter | Target |
|---|---|
| Peak (Cmax) | 56–64 µg/mL (once-daily); >30 µg/mL minimum for efficacy |
| Trough | <4–5 µg/mL (to minimize toxicity) |
| Cmax:MIC ratio | ≥8–10 (for concentration-dependent killing) |
Serum concentrations range 20–35 µg/mL following a 7.5 mg/kg dose (Goodman & Gilman's).
Renal Dose Adjustment (CKD)
Amikacin is renally cleared and nephrotoxic — dose reduction is mandatory in CKD.
| CrCl (mL/min) | Strategy |
|---|---|
| >80 | Normal dose (15 mg/kg OD) |
| 50–80 | Extend interval or reduce dose proportionally |
| 25–50 | Reduce to ~50% of normal daily dose |
| <25 | Reduce dose proportionally to remaining kidney function; extend interval >24 h |
| Dialysis | Supplemental dose after each session; monitor levels |
Rule of thumb: With X% remaining kidney function (GFR ~X mL/min), reduce total daily dose to X% of normal.
- Minimum effective dose: ≥7.5 mg/kg per administration (to still achieve adequate peak)
- Target peak: >30 µg/mL in CKD patients
- Extend the dosing interval rather than reducing the individual dose, to maintain efficacy peaks.
Weight-Based Dosing Adjustments (Obesity)
- Use Ideal Body Weight (IBW) in normal patients
- In obese patients (ABW >120% of IBW): use Adjusted Dosing Weight (ADjBW)
- AdjBW = IBW + 0.4 × (ABW – IBW)
Route of Administration
- IV (infuse over 30–60 minutes) or IM
- Intravitreal (ophthalmology): different formulation/dilution — 0.4 mg/0.1 mL (much lower dose)
Therapeutic Drug Monitoring (TDM)
TDM is essential due to narrow therapeutic index:
- Monitor peak (drawn 30–60 min after end of infusion) and trough (pre-dose)
- Routine monitoring not required if therapy <48 hours with normal renal function
- Mandatory with CKD, elderly, changing renal function, concurrent nephrotoxins (NSAIDs, vancomycin, contrast, etc.)
Toxicity
- Nephrotoxicity — reduced with once-daily dosing; monitor SCr every 2–3 days
- Ototoxicity (cochlear > vestibular) — cumulative and potentially irreversible
- Neuromuscular blockade — caution with anesthetics/muscle relaxants
Sources: Harrison's Principles of Internal Medicine 22E (2025); Comprehensive Clinical Nephrology, 7th Ed.; Goodman & Gilman's Pharmacological Basis of Therapeutics
This is a shared conversation. Sign in to Orris to start your own chat.