From the Guidelines
I would not recommend the amikacin dosing of 960 mg IM daily for 5 days for this patient without proper therapeutic drug monitoring and consideration of renal function. For a patient weighing 141 lbs (64 kg), the appropriate amikacin dose would be approximately 15 mg/kg/day, which equals about 960 mg daily, as per the guidelines from the American Thoracic Society 1. However, it's crucial to consider the patient's ideal body weight and monitor serum levels, particularly trough levels, to ensure they remain below 5-10 mcg/mL due to the risk of nephrotoxicity and ototoxicity.
Key Considerations
- The medication should be dosed based on ideal body weight, and serum levels should be monitored 1.
- Renal function should be assessed before starting therapy and monitored throughout treatment 1.
- The 5-day duration may be appropriate depending on the infection being treated, but this should be determined based on clinical response and the specific indication.
- Baseline audiometry and renal function tests should be performed before initiating amikacin therapy.
- Consider consulting with a pharmacist for precise dosing calculations to minimize the risk of adverse effects.
Dosing and Administration
- The recommended dose for adults is 15 mg/kg per day, with a maximum of 1.0 g/day 1.
- For patients over 59 years old, the dose should be reduced to 10 mg/kg per day 1.
- In cases of renal insufficiency, the dosing frequency should be reduced 1.
From the FDA Drug Label
The recommended dosage for adults, children and older infants with normal renal function is 15 mg/kg/day divided into 2 or 3 equal doses administered at equally-divided intervals, i.e., 7.5 mg/kg q12h or 5 mg/kg q8h. DOSAGE GUIDELINES ADULTS AND CHILDREN WITH NORMAL RENAL FUNCTION Patient WeightDosage lbskg7.5 mg/kg5 mg/kg q12hORq8h ... 143 65 487.5 mg 325 mg 154 70 525 mg 350 mg 165 75 562. 5 mg 375 mg 176 80 600 mg 400 mg 187 85 637.5 mg 425 mg 198 90 675 mg 450 mg 209 95 712. 5 mg 475 mg 220 100 750 mg 500 mg
For a patient weighing 141 lbs, the recommended dose is between 487.5 mg and 562.5 mg per dose, given the patient's weight is between 143 lbs (65 kg) and 154 lbs (70 kg). Given the patient is to receive 960 mg IM qd x5days, this dose is higher than the recommended dose. Amikacin 960 mg IM qd x5days is not appropriate for this patient. 2
From the Research
Amikacin Dosing
- The patient's weight is 141 Lbs, which is approximately 64 kg.
- The prescribed dose is 960 mg IM qd x 5 days, which is approximately 15 mg/kg per day.
- According to the study 3, the dose stratification strategy for cancer patients with CLcr ≥ 60 mL/min includes regimens of 20 mg/kg (q24h), 25 mg/kg (q24h), 25 mg/kg (q48h), and 30 mg/kg (q72h).
- The prescribed dose of 15 mg/kg per day is lower than the recommended doses in the study 3.
- However, the study 4 suggests that the incidence of amikacin-induced nephrotoxicity is lower in noncritically ill patients, and therapeutic drug monitoring (TDM) may not be necessary in patients with normal kidney function.
- The study 5 compared the safety, pharmacokinetics, and efficacy of once-a-day amikacin versus conventional schedules in patients with pelvic inflammatory disease, and found that the once-a-day schedule was as efficacious as the conventional schedules and caused less renal and auditory alterations.
- The study 6 compared the nephrotoxic potential of amikacin and gentamicin in patients with normal baseline renal function, and found that gentamicin was significantly more nephrotoxic than amikacin.
Nephrotoxicity Risk
- The studies 4, 7, and 6 suggest that the risk of nephrotoxicity is lower in patients with normal baseline renal function.
- The study 7 found that N-acetylcysteine, a thiol-containing antioxidant, had a protective effect on nephrotoxicity induced by amikacin.
- The study 5 found that early phospholipiduria and auditory losses at high frequencies were significantly reduced with the once-a-day administration of amikacin compared to conventional schedules.