BLACK BOX WARNING
- nephrotoxicity
- ototoxicity
- neuromuscular blockade
amikacin
Brand: Amikin
⚠ BBW TDM Required Prototype: gentamicin
Drug Class: aminoglycoside antibiotic
Drug Family: antibiotic
Subclass: broad-spectrum aminoglycoside resistant to most aminoglycoside-modifying enzymes
Organ Systems: infectious-disease
Mechanism of Action
Binds 30S ribosomal subunit causing misreading and inhibition of translocation; amikacin's chemical structure confers resistance to most aminoglycoside-inactivating enzymes, making it the aminoglycoside of last resort for resistant gram-negative infections.
30S ribosomal subunit
Indications
- serious gram-negative infections resistant to gentamicin and tobramycin
- hospital-acquired pneumonia and VAP (gram-negative)
- urinary tract infections (serious)
- NTM infections (Mycobacterium abscessus)
- combination therapy for MDR Acinetobacter baumannii
Contraindications
- aminoglycoside hypersensitivity
- pregnancy (ototoxicity risk)
Adverse Effects
Common
- nephrotoxicity
- ototoxicity (vestibular and cochlear)
- elevated BUN/creatinine
Serious
- irreversible hearing loss
- vestibular toxicity (vertigo, nystagmus)
- acute kidney injury
- neuromuscular blockade
Pharmacokinetics (ADME)
| Absorption | IV/IM only |
| Distribution | extracellular; poor CNS penetration |
| Metabolism | not metabolized |
| Excretion | renal (unchanged) |
| Half-life | 2–3 hours (normal renal function) |
| Onset | immediate (IV) |
| Peak | 30–90 min post-infusion |
| Duration | 8–24 hours |
| Protein Binding | 0–10% |
| Vd | low |
Drug Interactions
| Drug / Agent | Mechanism | Severity |
|---|---|---|
| loop diuretics | additive ototoxicity | major |
| vancomycin/colistin | additive nephrotoxicity | major |
| neuromuscular blocking agents | enhanced neuromuscular blockade; respiratory depression | major |
Nursing Considerations
- Monitor amikacin peaks (goal 20–35 mcg/mL for traditional dosing or 56–64 mcg/mL for extended-interval) and troughs (<5 mcg/mL traditional; undetectable extended-interval) — obtain timing precisely.
- Monitor serial BUN, SCr, and urine output; assess for ototoxicity with audiometry and vestibular testing when therapy extends beyond 7 days.
- Avoid concurrent nephrotoxic agents; if loop diuretics are required, separate dosing times and monitor closely.
- Extended-interval (high-dose once-daily) dosing maximizes peak-dependent killing and may reduce nephrotoxicity; verify pharmacy-determined dosing strategy.
Clinical Pearls
- Amikacin is the aminoglycoside least susceptible to enzymatic inactivation, because its hydroxyl and amino groups that are targets of aminoglycoside-modifying enzymes are protected by hydroxyl-butanoyl substitution.
- In the context of MDR and XDR gram-negative infections, amikacin is often the only aminoglycoside with in vitro activity, though carbapenem-resistant organisms require combination regimens.
Safety Profile
Pregnancy use-with-caution
Lactation use-with-caution
Renal Adjustment Required
Hepatic Adjustment Not required
TDM Required
Concordance Terms
Cross-referenced clinical concepts — click any term to see all content where it appears.