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Paul A. Pham Pharm.D. and John G. Bartlett M.D.
12-14-2009
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Available formulation in Zambia: Powder for injection: 1000 mg vial.
- In combination with a penicillin or cephalosporin, amikacin generally recommended for initial management of life-threatening infections likely to be caused by Gram-negative organisms resistant to gentamicin or tobramycin (e.g. septicaemia).
- Complicated UTI due to resistant aerobic Gram-negative organisms: amikacin 15 mg/kg IV q24h.
Zambia Information Author: Paul A. Pham, Pharm. D.
- Amikacin sulfate indicated in the short-term treatment of serious infections due to susceptible organisms. [With the exception of uncomplicated UTI, aminoglycosides are generally used in combination for treatment of ].
- Bacterial septicemia (including neonatal sepsis)
- Respiratory tract infections
- Bones and joint infections
- Central nervous system infections
- Skin and soft tissue infections
- Intra-abdominal infections
- Burns
- Post-operative infections
- Complicated and recurrent urinary tract infections.
- Pneumonia, Hospital-Acquired (in combination with a beta-lactam, beta-lactam/beta-lactamase inhibitor, or a 3rd/4th generation cephalosporin)
brand
name
| generic
| Mfg
| brand
forms
| cost*
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| Amikacin | Amikacin sulfate | ~generic manufacturers | IV
vial
1000mg/4mL | $16.05 |
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| IV
vial
100mg/2mL | $8.13 |
|
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| IV
vial
500mg/2mL | $8.13 |
*Prices represent cost per unit specified and are representative of "Average Wholesale Price" (AWP).
AWP Prices were obtained and gathered by Lakshmi Vasist Pharm D using the Red Book, manufacturer's
information, and the McKesson database.
^Dosage is indicated in mg unless otherwise noted.
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Once daily dosing: 15-20mg/kg IV. Therapeutic drug monitoring generally not recommended. Consider trough in patients at risk for nephrotoxicity (ICU pts, elderly, and concomitant nephrotoxin). Target trough <4 mcg/ml. Don't use once daily dosing in pts w/ unstable renal fxn, CrCl <60ml/min, endocarditis, meningitis, or increased Vd (pregnancy, ascites, edema).
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Traditional dosing (mild-moderate infections): 8mg/kg load, then 7mg/kg IV q8h OR 7.5-10 mg/kg IV q12h (goal peak > 20-30 mcg/ml and trough <10mcg/ml).
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Traditional dosing (severe infections, e.g. Pseudomonas, pneumonia): 8-12 mg/kg load, then 8 mg/kg IV q8h (goal peak >25-35 mcg/ml and trough <10 mcg/ml).
- Consider a higher loading dose and obtain a peak and trough after first dose in severe infections (+/- diffuse edema, ascites, shock, burns, CF pts, and pregnancy) in order to calculate patient-specific pharmacokinetic dose. Doses need to be adjusted based on changing renal function and/or volume status.
- Troughs should be obtained (generally after 3rd dose) immediately before next dose.
- Peak should be obtained 30 mins after the end of a 30 mins infusion (generally after 3rd dose).
- For obese patients: use calculated lean body weight plus 40% of excess fat (Dosing Body Weight (DBW) = Ideal Body Weight (IBW) + 0.4 (Actual body weight-IBW) .
- IBW= 50kg (for males) OR 45.5kg (for females) PLUS (2.3 x inches over 5ft).
- Intraventricular or intrathecal administration: amikacin 15 mg q24h (range 10-50 mg). Note: preservative free amikacin is not available. Sodium bisulfite preservative may increase risk of neurotoxicities (e.g seizure, aseptic meningitis, and radicular pain). Use IT amikacin only if organism is resistant to gentamicin and tobramycin (both available preservative free).
Standard loading dose for all levels of renal function. GRF>70 ml/min: Use standard dose. GFR 50-69 ml/min: calculated GFR x 0.18 = "mg/kg" q12h (Ex. for GFR 56 ml/min: 56 x 0.18 = "10" mg/kg q12h. Monitor peak and trough.
Standard loading dose for all levels of renal function. GFR 40-49 ml/min: calculated GFR x 0.18 = "mg/kg" q12h (Ex. for GFR 45 ml/min: 45 x 0.18 = "8" mg/kg q12h). GFR 20-39: calculated GFR x 0.36 = "mg/kg" q24h. Monitor peak and trough.
Standard loading dose for all levels of renal function. GFR <20 ml/min: 10 mg/kg x 1, then redose when level <2 mcg/mL. Monitor peak and trough.
Standard loading dose, then 8 mg/kg post-HD (treatment doses). Peak (measure 2 hours-post dose, target 25-35 mcg/mL) and trough (before next HD session, depending on residual renal function, expect 12-16 mcg/mL).
9-20 mg per Liter of dialysate exchange per day. Aminoglycosides given for prolonged periods to patients receiving continuous peritoneal dialysis have been associated with high rates of ototoxicity.
CVVH or CVVHD: loading dose 10-12 mg/kg, then 8mg/kg q24-48 (measure peak 2 hours-post dose, target 25-35 mcg/mL). Check a 24-h concentration (redose <10 mcg/mL).
- Renal failure (usually reversible): risk factors include older patients, preexisting renal and hepatic disease, volume depletion, traditional Q8h dosing, large doses, concomitant nephrotoxic drug (including vancomycin), and length of therapy (most important). Controversial but trough level may be associated with nephrotoxicity.
- Irreversible vestibular toxicity (4-6%). Most patient compensate with visual and proprioceptive cues. Monitor for nausea, vomiting, nystagmus and vertigo (exacerbated in the dark).
- Irreversible cochlear toxicity (3-14%). Risk factors include repeated exposure (cumulative dose and duration of therapy), genetic predisposition, renal impairment, specific aminoglycoside (neomycin>streptomycin>gentamicin>tobramycin>amikacin>netilmicin), elderly, age, bacteremia, hypovolemia, degree of temperature elevation and liver dysfunction (JID 1984:149:23-30). 62% of hearing lost were at frequency above 9kHz (high pitch) at a mean of 9 days of therapy (JID 1992; 165:1026-1032).
- Genetic predisposition may be present in some cases of vestibular and cochlear toxicity. Check family Hx for aminoglycoside ototoxicity.
- Monitor for ototoxicity in any patients receiving >3 days of aminoglycoside. Vestibular toxicity monitoring: check baseline visual acuity using a Snellen pocket card. After 3 days of aminoglycoside, have patient shake head (side to side) while reading a line. Early sign of ototoxicity if patient loses 2 lines of visual acuity. Check Romberg sign. Cochlear toxicity monitoring: audiology test.
- Neuromuscular blockade (especially with myasthenia or Parkinsons and rapid infusion of large aminoglycoside doses).
- Allergic reaction (secondary to sulfites in some formulations).
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Penicillins: in vitro inactivation. Do not mix or run in the same tubing.
- Cephalothin: increased risk of nephrotoxicity.
- Nondepolarizing muscle relaxants (atracurium, pancuronium, tubocurarine, gallamine triethiodide): possible enhanced action of nondepolarizing muscle relaxant resulting in possible respiratory depression.
- Loop diuretics (bumetanide, furosemide, ethacrynic acid, torsemide): cochlear toxicity (esp. w/ ethacrynic acid). Avoid co-administration.
- Other nephrotoxic agents (e.g amphotericin B, foscarnet, cidofovir, and IV contrast dyes): additive nephrotoxicity. Avoid co-administration.
- Vancomycin: increased risk of nephrotoxicity.
- MIC sensitive breakpoint for Enterobacteriaceae and Gram-negative non-lactose fermenters including P. aeruginosa is 16 mcg/mL.
Amikacin is an aminoglycoside that is active against many gram-negative bacteria resistant to gentamicin and tobramycin. In many institutions, drug has the most predictable activity against . Amikacin should be restricted to infections with organisms resistant to other aminoglycosides. Desired peak 25-35 mcg/ml (high peak for serious, pulmonary, and pseudomonal infections).
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