How to administer amikacin (intramuscularly)?

How to Administer Amikacin Intramuscularly

For intramuscular administration of amikacin, use a dose of 15 mg/kg/day for adults, which can be divided into 2 or 3 equal doses (7.5 mg/kg every 12 hours or 5 mg/kg every 8 hours). 1

Standard Dosing Procedure

• Calculate the dose based on the patient's pretreatment body weight 1
• For adults with normal renal function, administer 15 mg/kg/day divided into 2 or 3 equal doses (7.5 mg/kg every 12 hours or 5 mg/kg every 8 hours) 1, 2
• The total daily dose should not exceed 1.5 grams 2, 1
• For patients over 59 years of age, reduce the dose to 10 mg/kg/day 2, 3

Administration Technique

• Use proper aseptic technique when preparing and administering the injection 1
• Select an appropriate injection site (typically the gluteal muscle or lateral thigh) 1
• Insert the needle at a 90-degree angle into the muscle 1
• Aspirate to ensure the needle is not in a blood vessel before injecting the medication 1
• Inject the medication slowly to minimize discomfort 1
• Apply gentle pressure to the injection site after removing the needle 1

Dosage Adjustments for Special Populations

• For patients with renal impairment, maintain the mg/kg dose at 12-15 mg/kg but reduce the dosing frequency 2, 3
• If creatinine clearance is not available, calculate the dosing interval by multiplying the patient's serum creatinine by 9 (e.g., if serum creatinine is 2 mg/dL, administer every 18 hours) 1
• For hemodialysis patients, administer the drug after dialysis 3, 4
• In obese patients, adjust the dose using ideal body weight + 40% of excess weight 3

Monitoring Requirements

• Measure baseline renal function (serum creatinine) before starting therapy 1, 2
• Monitor serum amikacin levels when possible, targeting peak levels of 25-35 mg/L and trough levels <5 mg/L 3, 1
• Perform baseline audiogram and vestibular testing before treatment 2
• Conduct monthly assessments of renal function and question patients about auditory or vestibular symptoms 2
• Repeat audiogram and vestibular testing if symptoms of eighth nerve toxicity develop 2

Important Precautions

• Be alert for signs of ototoxicity (hearing loss, tinnitus, vertigo) and nephrotoxicity (decreased urine output, increased serum creatinine) 2, 3
• The risk of ototoxicity increases with age, use of loop diuretics, and cumulative doses above 100-120g 2
• Circumoral paresthesias immediately after injection are relatively common but transient 2
• The usual duration of treatment is 7-10 days; longer treatment requires careful monitoring of serum levels and renal/auditory function 1
• Clinical response should occur within 24-48 hours; if no response is seen within 3-5 days, reevaluate therapy 1

Common Pitfalls to Avoid

• Administering doses that exceed 1.5 grams per day, regardless of weight 2, 1
• Failing to adjust dosing in elderly patients or those with renal impairment 2, 3
• Not monitoring serum levels, which can lead to toxicity or treatment failure 3, 1
• Continuing therapy beyond 10 days without careful monitoring of serum levels and organ function 1
• Administering amikacin before dialysis in hemodialysis patients, which results in premature drug removal 4