Tobramycin
TOBREX
What it isAminoglycoside inhibiting the 30S ribosomal subunit; Gram-negative and pseudomonal infection, inhaled in cystic fibrosis.
Why this oneBetter antipseudomonal activity than gentamicin, and the inhaled route delivers high airway concentrations with little systemic exposure.
What limits itNephrotoxicity and irreversible ototoxicity, so levels and function are monitored. Once-daily dosing exploits the post-antibiotic effect.
FDA-approved for
- Pseudomonas infections (1975)
- cystic fibrosis (inhaled) (1997)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Cystic fibrosis, Pseudomonas aeruginosa | Adults & peds ≥6 yr | Four 28 mg capsules (112 mg) inhaled BID | 112 mg BID, 28 days on / 28 days off |
Renal Undefined (not studied in serum creatinine ≥2 mg/dL or BUN ≥40; monitor renal function)
Hepatic No adjustment needed (tobramycin not metabolized)
Dosage not adjusted by weight; each dose ≥6 hours apart
Instructions
- For oral inhalation only with the Podhaler device; do not swallow capsules
- Inhale contents of four 28 mg capsules twice daily
- Administer doses as close to 12 hours apart as possible; not less than 6 hours apart
- Cycle 28 days on then 28 days off
- Store capsules in blister; remove immediately before use
- If multiple inhaled therapies, take TOBI Podhaler last
Contraindications
- Known hypersensitivity to any aminoglycoside
Cautions
- Bronchospasm
- Ototoxicity (hearing loss, tinnitus); risk with mitochondrial MT-RNR1 variants
- Nephrotoxicity (aminoglycoside class effect)
- May aggravate muscle weakness in neuromuscular disorders
- Embryo-fetal toxicity
- Monitor serum levels with concomitant systemic aminoglycosides
Adverse reactions
- Cough
- Lung disorder, productive cough, dyspnea
- Oropharyngeal pain, dysphonia
- Hemoptysis
- Pyrexia, headache
Pregnancy Aminoglycosides can cause fetal harm; systemic absorption after inhalation minimal; advise of potential risk
Lactation No data for inhaled form; systemic tobramycin present in human milk; monitor infant for loose/bloody stools and thrush
⚠ BOXED WARNINGS
- Nephrotoxicity and ototoxicity
- Neuromuscular blockade
Cost, est. cash$10–$500/bag or supply
Generic entry1984
Classes and tags
Clinical profile
Legacy pregnancy categoryD
Defining liabilityUsually well tolerated at replacement doses; excessive dosing can cause agent-specific metabolic or organ toxicity.
Mechanism of action: Tobramycin ballicule
