Tobrex® Ointment
Tobramycin 0.3% · ophthalmic ointment
Antibiotic
Approved uses
Bacterial blepharitis and conjunctivitis
Half-inch ribbon into the affected eye(s) 2 or 3 times per day (mild to moderate disease)
97% cured or improved after 10 days, comparable to gentamicin ointment.
Severe external ocular infection
Half-inch ribbon into the affected eye(s) every 3 to 4 hours until improvement, then reduce frequency before discontinuing
Contraindications
Known hypersensitivity to tobramycin or any component of the formulation.
Available FormsOphthalmic ointment, 3.5 g aluminum tube, 0.3% (3 mg/g)
Mechanism of ActionBactericidal aminoglycoside acting at the bacterial 30S ribosomal subunit to block protein translation. In vitro activity spans gram-positive and gram-negative ocular pathogens, including penicillin-resistant staphylococci and Pseudomonas aeruginosa, and some gentamicin-resistant organisms stay susceptible.
Warnings & Precautions
- Intraocular injection: Not for injection into the eye; topical ophthalmic formulation only.
- Aminoglycoside hypersensitivity: Reactions range from local effects to generalized erythema, itching, urticaria, skin rash, anaphylaxis, anaphylactoid or bullous reactions; discontinue if sensitivity occurs.
- Aminoglycoside cross-sensitivity: Cross-sensitivity to other aminoglycoside antibiotics may occur; discontinue and institute appropriate therapy if hypersensitivity develops.
- Superinfection: Prolonged use may result in overgrowth of nonsusceptible organisms, including fungi; start appropriate therapy if superinfection occurs.
- Corneal epithelial toxicity: Tobramycin solution was among the three most toxic of eight topical antibiotic solutions tested in a rabbit corneal wound-healing model; the ointment vehicle was not studied, so prolonged use over an epithelial defect warrants caution.
- Systemic aminoglycoside class effects: Neurotoxicity, ototoxicity and nephrotoxicity have occurred with systemic aminoglycoside therapy, which may also aggravate muscle weakness in neuromuscular disorders such as myasthenia gravis or Parkinson disease.
- Contact lens wear: Not advised while signs and symptoms of ocular infection are present.
Common Side Effects
- Ocular: Hypersensitivity and localized ocular toxicity, including lid itching and swelling and conjunctival erythema; fewer than 3 of 100 treated patients.
- Systemic: Anaphylactic reaction, Stevens-Johnson syndrome, erythema multiforme; postmarketing reports.
Pregnancy & LactationPregnancy: Reproduction studies in 3 animal species at up to 33 times the human systemic dose showed no impaired fertility and no fetal harm; no adequate, well-controlled studies in pregnant women, so use only if clearly needed.
Lactation: Given the potential for adverse reactions in nursing infants, decide between discontinuing nursing and discontinuing the drug.
Pediatric UseNot established below age 2 months.