Generic name: tobrex
Availability: Prescription only
Pregnancy & Lactation: Risk data available
Brand names: Tobrasol, Tobrex, Tobramycin ophthalmic
What is Tobramycin (eent) (monograph)?
Introduction
Antibacterial; aminoglycoside.
Uses for Tobramycin (EENT)
Bacterial Ophthalmic Infections
Topical treatment of superficial infections of the eye caused by susceptible bacteria.
Mild, acute bacterial conjunctivitis often resolves spontaneously without anti-infective treatment. Although topical ophthalmic anti-infectives may shorten time to resolution and reduce severity and risk of complications, avoid indiscriminate use of topical anti-infectives. Treatment of acute bacterial conjunctivitis generally is empiric; use of a broad-spectrum topical ophthalmic antibacterial usually recommended. In vitro staining and/or cultures of conjunctival material may be indicated in management of recurrent, severe, or chronic purulent conjunctivitis or when acute conjunctivitis does not respond to initial empiric topical treatment.
Because bacterial keratitis may be associated with subsequent loss of vision as the result of corneal scarring or topographic irregularities and because untreated or severe bacterial keratitis may result in corneal perforation with potential for endophthalmitis and possible loss of the eye, optimal management involves rapid evaluation and diagnosis, timely initiation of treatment, and appropriate follow-up. Treatment of community-acquired bacterial keratitis generally is empiric; use of a broad-spectrum topical ophthalmic antibacterial usually recommended. Subconjunctival anti-infectives may be necessary if scleral spread or perforation is imminent. In vitro staining and/or cultures of corneal material are indicated in management of keratitis involving corneal infiltrates that are central, large, and extend to the middle to deep stroma; when keratitis is chronic or unresponsive to a broad-spectrum topical anti-infective; or when atypical features suggest fungal, amebic, or mycobacterial infection.
Ocular Inflammation
Fixed-combination ophthalmic preparations containing tobramycin and a corticosteroid (i.e., dexamethasone or loteprednol etabonate): Topical treatment of corticosteroid-responsive ocular conditions when a corticosteroid indicated and superficial bacterial ocular infection or risk of such infection exists.
Although manufacturers state that use of a fixed-combination ophthalmic preparation containing an anti-infective and a corticosteroid may be indicated in ocular inflammatory conditions when risk of superficial ocular infection is high or when potentially dangerous numbers of bacteria are expected to be present in the eye, experts state avoid use of such preparations in patients with bacterial conjunctivitis because of risk of potentiating the infection.
Consider that use of fixed-combination ophthalmic preparations containing an anti-infective and a corticosteroid may mask clinical signs of bacterial, fungal, or viral infections; prevent recognition of ineffectiveness of the anti-infective; and/or increase IOP. (See Use of Fixed Combinations Containing Corticosteroids under Cautions.)
Tobramycin (EENT) Dosage and Administration
Administration
Ophthalmic Administration
Apply tobramycin ophthalmic ointment or solution topically to the eye.
Apply fixed-combination ophthalmic ointment or suspensions containing tobramycin and a corticosteroid (i.e., dexamethasone or loteprednol) topically to the eye.
For topical ophthalmic use only; do not inject directly into eye.
Avoid contaminating container tip with material from any source.
Shake fixed-combination ophthalmic suspensions well prior to use.
Dosage
Pediatric Patients
Bacterial Ophthalmic Infections
Ophthalmic
Tobramycin 0.3% (ophthalmic ointment) in children ≥2 months of age: Apply approximately 1.25-cm (½-inch) ribbon in affected eye(s) 2 or 3 times daily. For severe infections, apply to affected eye(s) every 3–4 hours initially.
Tobramycin 0.3% (ophthalmic solution) in children ≥2 months of age: Instill 1 or 2 drops into affected eye(s) every 4 hours. For severe infections, instill 2 drops into affected eye(s) every hour initially.
When improvement occurs, taper dosage by decreasing frequency until drug is discontinued.
Usual duration of topical anti-infective treatment for bacterial conjunctivitis is 5–10 days; 5–7 days usually adequate for mild bacterial conjunctivitis.
Ocular Inflammation
Ophthalmic
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic ointment) in children ≥2 years of age: Apply approximately 1.25-cm (½-inch) ribbon into conjunctival sac of affected eye(s) up to 3 or 4 times daily.
Tobramycin 0.3% and dexamethasone 0.05% (ophthalmic suspension) in children ≥2 years of age: Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic suspension) in children ≥2 years of age: Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
If no improvement after 2 days, reevaluate patient. When improvement occurs, taper dosage by decreasing frequency until drug is discontinued. Do not discontinue prematurely.
Adults
Bacterial Ophthalmic Infections
Ophthalmic
Tobramycin 0.3% (ophthalmic ointment): Apply approximately 1.25-cm (½-inch) ribbon to affected eye(s) 2 or 3 times daily. For severe infections, apply to affected eye(s) every 3–4 hours initially.
Tobramycin 0.3% (ophthalmic solution): Instill 1 or 2 drops into affected eye(s) every 4 hours. For severe infections, instill 2 drops into affected eye(s) every hour initially.
When improvement occurs, taper dosage by decreasing frequency until drug is discontinued.
Usual duration of topical anti-infective treatment for bacterial conjunctivitis is 5–10 days; 5–7 days usually adequate for mild bacterial conjunctivitis.
Ocular Inflammation
Ophthalmic
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic ointment): Apply approximately 1.25-cm (½-inch) ribbon into conjunctival sac of affected eye(s) up to 3 or 4 times daily.
Tobramycin 0.3% and dexamethasone 0.05% (ophthalmic suspension): Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic suspension): Instill 1 or 2 drops into conjunctival sac of affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and loteprednol etabonate 0.5% (ophthalmic suspension): Instill 1 or 2 drops into conjunctival sac of affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 1–2 hours if necessary.
If no improvement after 2 days, reevaluate patient. When improvement occurs, taper dosage by decreasing frequency until drug is discontinued. Do not discontinue prematurely.
Warnings
Contraindications
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Tobramycin ophthalmic ointment or solution: Hypersensitivity to tobramycin or any ingredient in the formulation.
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Fixed-combination ophthalmic preparations containing tobramycin and a corticosteroid (i.e., dexamethasone or loteprednol): Known or suspected hypersensitivity to any ingredient in the formulation. Also, patients with viral diseases of the cornea and conjunctiva, including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, and varicella; mycobacterial infections of the eye; or fungal diseases of ocular structures.
Warnings/Precautions
Sensitivity Reactions
Hypersensitivity
Hypersensitivity reported. Sensitization to tobramycin may result from topical application.
Cross-allergenicity occurs among the aminoglycosides.
If sensitivity reaction occurs, immediately discontinue and initiate appropriate therapy.
Superinfection
Prolonged use may result in overgrowth of nonsusceptible organisms, including fungi.
If superinfection occurs, discontinue the drug and institute appropriate therapy.
Precautions Related to Ophthalmic Administration
If tobramycin is administered topically in conjunction with systemic aminoglycoside therapy, monitor serum aminoglycoside concentrations.
Manufacturers caution that ophthalmic ointments may delay corneal healing.
Do not wear contact lenses during treatment or if any signs or symptoms of bacterial ocular infection are present.
Use of Fixed Combinations Containing Corticosteroids
When ophthalmic preparations containing tobramycin in fixed combination with a corticosteroid (i.e., dexamethasone or loteprednol) used, consider cautions, precautions, and contraindications associated with EENT corticosteroids.
Provide initial prescriptions for fixed-combination ophthalmic preparations containing a corticosteroid or renewal prescriptions (beyond 8 g of ophthalmic ointment or beyond 20 mL of ophthalmic solution) only after examining patient with slit lamp microscopy and, when appropriate, fluorescein staining.
Prolonged use of fixed-combination ophthalmic preparations containing a corticosteroid may result in glaucoma, with optic nerve damage, defects in visual acuity and fields of vision, and posterior subcapsular cataract formation. If such preparation used for ≥10 days, routinely monitor IOP, even though this may be difficult in children and uncooperative patients. Use fixed combinations containing a corticosteroid with caution in patients with glaucoma; routinely check IOP in such patients.
Use of fixed-combination ophthalmic preparations containing a corticosteroid after cataract surgery may delay healing and increase incidence of bleb formation.
Use of topical corticosteroids in patients with thin corneal and scleral tissue may result in perforation.
Prolonged use of fixed-combination ophthalmic preparations containing a corticosteroid may suppress host responses and increase risk of secondary ocular infections. Use in patients with acute purulent conditions of the eye may mask infection or enhance existing infection.
May prolong course and exacerbate severity of many viral infections of the eye (including herpes simplex). Use with great caution in patients with herpes simplex.
Consider possibility of fungal infections of the cornea after prolonged use of ophthalmic preparations containing a corticosteroid. Perform fungal cultures when appropriate.
Specific Populations
Pregnancy
No adequate and well-controlled studies using ophthalmic preparations containing tobramycin in pregnant women.
Use tobramycin ophthalmic ointment or solution during pregnancy only if clearly needed.
Use fixed-combination ophthalmic preparations containing tobramycin and a corticosteroid (i.e., dexamethasone or loteprednol etabonate) during pregnancy only if potential benefits justify potential risks to fetus.
Lactation
Discontinue nursing or the drug, taking into account importance of the drug to the woman.
Manufacturers state use fixed-combination ophthalmic preparations containing tobramycin and a corticosteroid with caution in nursing women.
Pediatric Use
Tobramycin ophthalmic ointment or solution: Safety and efficacy not established in children <2 months of age.
Fixed-combination ophthalmic preparations containing tobramycin and dexamethasone: Safety and efficacy not established in children <2 years of age.
Fixed-combination ophthalmic preparation containing tobramycin and loteprednol etabonate: Efficacy not established in pediatric patients.
Geriatric Use
No overall differences in safety and efficacy observed between geriatric and younger adults.
Common Adverse Effects
Hypersensitivity and localized ocular toxicity (pruritus, edema of the eyelid, conjunctival erythema).
How should I use Tobramycin (eent) (monograph)
Administration
Ophthalmic Administration
Apply tobramycin ophthalmic ointment or solution topically to the eye.
Apply fixed-combination ophthalmic ointment or suspensions containing tobramycin and a corticosteroid (i.e., dexamethasone or loteprednol) topically to the eye.
For topical ophthalmic use only; do not inject directly into eye.
Avoid contaminating container tip with material from any source.
Shake fixed-combination ophthalmic suspensions well prior to use.
Dosage
Pediatric Patients
Bacterial Ophthalmic Infections
Ophthalmic
Tobramycin 0.3% (ophthalmic ointment) in children ≥2 months of age: Apply approximately 1.25-cm (½-inch) ribbon in affected eye(s) 2 or 3 times daily. For severe infections, apply to affected eye(s) every 3–4 hours initially.
Tobramycin 0.3% (ophthalmic solution) in children ≥2 months of age: Instill 1 or 2 drops into affected eye(s) every 4 hours. For severe infections, instill 2 drops into affected eye(s) every hour initially.
When improvement occurs, taper dosage by decreasing frequency until drug is discontinued.
Usual duration of topical anti-infective treatment for bacterial conjunctivitis is 5–10 days; 5–7 days usually adequate for mild bacterial conjunctivitis.
Ocular Inflammation
Ophthalmic
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic ointment) in children ≥2 years of age: Apply approximately 1.25-cm (½-inch) ribbon into conjunctival sac of affected eye(s) up to 3 or 4 times daily.
Tobramycin 0.3% and dexamethasone 0.05% (ophthalmic suspension) in children ≥2 years of age: Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic suspension) in children ≥2 years of age: Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
If no improvement after 2 days, reevaluate patient. When improvement occurs, taper dosage by decreasing frequency until drug is discontinued. Do not discontinue prematurely.
Adults
Bacterial Ophthalmic Infections
Ophthalmic
Tobramycin 0.3% (ophthalmic ointment): Apply approximately 1.25-cm (½-inch) ribbon to affected eye(s) 2 or 3 times daily. For severe infections, apply to affected eye(s) every 3–4 hours initially.
Tobramycin 0.3% (ophthalmic solution): Instill 1 or 2 drops into affected eye(s) every 4 hours. For severe infections, instill 2 drops into affected eye(s) every hour initially.
When improvement occurs, taper dosage by decreasing frequency until drug is discontinued.
Usual duration of topical anti-infective treatment for bacterial conjunctivitis is 5–10 days; 5–7 days usually adequate for mild bacterial conjunctivitis.
Ocular Inflammation
Ophthalmic
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic ointment): Apply approximately 1.25-cm (½-inch) ribbon into conjunctival sac of affected eye(s) up to 3 or 4 times daily.
Tobramycin 0.3% and dexamethasone 0.05% (ophthalmic suspension): Instill 1 or 2 drops into affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and dexamethasone 0.1% (ophthalmic suspension): Instill 1 or 2 drops into conjunctival sac of affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 2 hours if necessary.
Tobramycin 0.3% and loteprednol etabonate 0.5% (ophthalmic suspension): Instill 1 or 2 drops into conjunctival sac of affected eye(s) every 4–6 hours. During initial 24–48 hours, 1 or 2 drops may be instilled every 1–2 hours if necessary.
If no improvement after 2 days, reevaluate patient. When improvement occurs, taper dosage by decreasing frequency until drug is discontinued. Do not discontinue prematurely.