How the dose is calculated
Amikacin is dosed in mg/kg/day. Extended-interval (once-daily) dosing is standard practice for most patients with normal renal function; traditional divided dosing is still used in neonates and select renal-impairment protocols. This is an injectable (IV/IM) antibiotic — no suspension volume conversion applies.
Typical dosing by indication
| Indication | Dose | Frequency | Max |
|---|---|---|---|
| Extended-interval | 15 mg/kg/day | once daily | 1500 mg/day |
| Traditional divided | 15 mg/kg/day | every 8h (3×/day) | 1500 mg/day |
Amikacin has a narrow therapeutic index — this calculator gives only a starting dose. Peak and trough (or single extended-interval) levels must be monitored and the dose/interval adjusted accordingly, because of real risks of nephrotoxicity and ototoxicity, particularly with prolonged courses.
Clinical use
- Amikacin is more resistant to many aminoglycoside-modifying enzymes than gentamicin or tobramycin, making it a useful option for infections caused by gentamicin-resistant Gram-negative organisms.
- Extended-interval (once-daily) dosing achieves the high peak concentration needed for bactericidal effect while allowing a drug-free trough period thought to reduce nephrotoxicity risk.
- Therapeutic drug monitoring (peak/trough or single extended-interval level) is essential given its narrow therapeutic index.
- Often reserved for multidrug-resistant Gram-negative infections (including some resistant tuberculosis regimens) rather than used as routine first-line empirical therapy.
Frequently asked questions
Why is amikacin used instead of gentamicin?
Amikacin resists many of the enzymes that bacteria use to inactivate gentamicin and tobramycin, so it's often reserved for infections caused by organisms already resistant to those other aminoglycosides.
Does amikacin need blood level monitoring?
Yes — like other aminoglycosides, its narrow therapeutic index and real risk of kidney and hearing toxicity mean peak/trough (or single extended-interval) levels are checked and the dose adjusted accordingly, especially beyond a few days of therapy.
Is amikacin available as a tablet or syrup?
No — amikacin is only available as an injectable (IV or IM) formulation; there is no oral tablet or suspension form.
What are the main risks of amikacin?
Nephrotoxicity (kidney injury) and ototoxicity (hearing/balance damage) are the main concerns, which is why dosing is weight-based, therapeutic monitoring is used, and treatment courses are kept as short as clinically appropriate.
References
- American Academy of Pediatrics Red Book — Aminoglycosides.
- British National Formulary for Children (BNFc) — Amikacin.
- World Health Organization. Companion Handbook — Multidrug-Resistant Tuberculosis Treatment.