Tobramycin/Dexamethasone Ophtalmic (Tobradex, Tobradex ST) is used to treat inflammation, corneal injury and bacterial infections in the external part of the eye.
Tobramycin is an aminoglycoside antibiotic. Dexamethasone is a type of cortisone and belongs to the group of medicines called corticosteroids.
 BRAND NAMES
- International: Tobradex
 MECHANISM OF ACTION
Tobramycin/Dexamethasone (Ophtalmic) is a topical antibiotic and corticosteroid combination.
Dexamethasone, a potent corticosteroid, suppresses the inflammatory response to chemical, immunological, or mechanical irritants.
The bactericidal activity of tobramycin is accomplished by specific inhibition of normal protein synthesis in susceptible bacteria.
For steroid-responsive inflammatory ocular conditions for which a corticosteroid is indicated and where bacterial eye infection or a risk of bacterial ocular infection exist.
Ocular steroids are indicated in inflammatory conditions of the palpebral and bulbar conjunctiva, cornea and anterior segment of the globe where the inherent risk of steroid use in certain infective conjunctivitides is accepted to obtain a diminution in edema and inflammation. They are also indicated in chronic anterior uveitis and corneal injury from chemical, radiation, thermal burns or penetration of foreign bodies.
- Ophthalmic suspension and ST ophthalmic suspension: One to two drops instilled into the conjunctival sac every four hours. During the initial 24 to 48 hours, the dosage may be increased to one or two drops every two hours. Frequency should be decreased gradually as warranted by improvement in clinical signs. Care should be taken not to discontinue therapy prematurely
- Ointment: Apply a small amount (approximately 1/2 inch ribbon) into the conjunctival sac(s) up to three or four times daily.
 DOSAGE FORMS AND STRENGTHS
- Ophthalmic suspension: it contains 3 mg/mL tobramycin and 1 mg/mL dexamethasone
- ST ophthalmic suspension: it contains 3 mg/mL tobramycin and 0.5 mg/mL dexamethasone ( ½ the concentration of dexamethasone compared to generic tobramycin/dexamethasone ophthalmic suspension formulations)
- Ointment: Each gram contains 3 mg (0.3%) tobramycin and 1 mg (0.1%) dexamethasone
- Viral diseases of the cornea and conjunctiva including epithelial herpes simplex keratitis (dendritic keratitis), vaccinia, and varicella
- Mycobacterial infection of the eye
- Fungal diseases of the eye
- Hypersensitivity to any component of the medication
 WARNINGS AND PRECAUTIONS
- Intraocular pressure (IOP) increase-Prolonged use of corticosteroids may result in glaucoma with damage to the optic nerve, defects in visual acuity and fields of vision. If Tobramycin/Dexamethasone (Ophtalmic) is used for 10 days or longer, IOP should be monitored.
- Sensitivity to topically applied aminoglycosides may occur.
- Prolonged use of corticosteroids may result in glaucoma, with damage to the optic nerve, defects in visual acuity and fields of vision, and posterior subcapsular cataract formation.
- Delayed healing: The use of steroids after cataract surgery may delay healing and increase the incidence of bleb formation. In those diseases causing thinning of the cornea or sclera, perforations have been known to occur with the use of topical steroids. The initial prescription and renewal of the medication order should be made by a physician only after examination of the patient with the aid of magnification such as slit lamp biomicroscopy and, where appropriate, fluorescein staining.
- Bacterial infections: Prolonged use of corticosteroids may suppress the host response and thus increase the hazard of secondary ocular infections. In acute purulent conditions, steroids may mask infection or enhance existing infection. If signs and symptoms fail to improve after 2 days, the patient should be re-evaluated.
- Viral infections: Employment of a corticosteroid medication in the treatment of patients with a history of herpes simplex requires great caution. Use of ocular steroids may prolong the course and may exacerbate the severity of many viral infections of the eye (including herpes simplex).
- Fungal infections: Fungal infections of the cornea are particularly prone to develop coincidentally with long-term local steroid application. Fungus invasion must be considered in any persistent corneal ulceration where a steroid has been used or is in use.
- If Tobramycin/Dexamethasone (Ophtalmic) is used in combination with systemic aminoglycoside antibiotics the patient should be monitored for total serum concentration of tobramycin.
 PREGNANCY AND LACTATION
- Pregnancy Category C (US). Tobramycin/Dexamethasone (Ophtalmic) should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
- Nursing Mothers: Caution should be exercised when Tobramycin/Dexamethasone (Ophtalmic) is administered to a nursing woman.
 SIDE EFFECTS
The most frequently reported treatment-related adverse reactions were eye pain, intraocular pressure increased, eye irritation, and eye pruritus occurring in less than 1% of patients.
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