tobramycin and dexamethasone

What is tobramycin and dexamethasone? How does it work (mechanism of action)?

TOBRADEX® ST (tobramycin / dexamethasone ophthalmic suspension 0.3%/0.05%) ophthalmic suspension is indicated for steroid-responsive inflammatory ocular conditions for which a corticosteroid is indicated and where superficial bacterial ocular infection or a risk of bacterial ocular infection exists.

Ocular steroids are indicated in inflammatory conditions of the palpebral and bulbar conjunctivacornea 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 or thermal burns, or penetration of foreign bodies.

The use of a combination drug with an anti-infective component is indicated where the risk of superficial ocular infection is high or where there is an expectation that potentially dangerous numbers of bacteria will be present in the eye.

The particular anti-infective drug in this product is active against the following common bacterial eye pathogens: Staphylococci, including S. aureus and S. epidermidis (coagulase-positive and coagulase-negative), including penicillin-resistant isolates. Streptococci, including some Group A and other beta-hemolytic species, some nonhemolytic species, and some Streptococcus pneumoniae. Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae, Enterobacter aerogenes, Proteus mirabilis, Morganella morganii , most Proteus vulgaris isolates, Haemophilus influenzae , H. aegyptius, Moraxella lacunata, Acinetobacter calcoaceticus and some Neisseria species.

The brand name for tobramycin and dexamethasone ophthalmic suspension is TOBRADEX®.

TOBRADEX® is not available in generic form. You need a prescription to obtain TOBRADEX®.  

What are Tobradex used for?

Tobradex (tobramycin) and dexamethasone ophthalmic suspension) is indicated for steroid responsive inflammatory ocular conditions for which a corticosteroid is indicated and where superficial bacterial ocular infection or a risk of bacterial ocular infection exist

What are the side effects of tobramycin and dexamethasone?

The most frequently reported side effects of Tobradex are: 

  • itching,
  • swelling of the eye lids, and
  • redness of the conjunctivae.

Other side effects include:


Pink Eye (Conjunctivitis) Symptoms, Causes, Treatments See Slideshow

What is the dosage for tobramycin and dexamethasone?

The recommended dose is one or two drops (solution or ointment) or one drop (suspension) into the conjunctival sac every four to six hours. The dosing interval may be reduced to every two hours during the initial 24 to 48 hours. The hands should be washed before each use of Tobradex or any eye medication. The head is tilted back, and the lower eye lid is pulled down with the index finger to form a pouch. The tip of the dropper should not touch the eye or eyelid. The bottle of Tobradex should be squeezed slightly to allow the prescribed number of drops (generally one or two drops) into the pouch. If the ointment is being used, a small strip (about 1cm or 1/2 inch) of ointment should be squeezed into the pouch. The eye should then be closed gently for one to two minutes without blinking.

Is tobramycin and dexamethasone safe to take if you are pregnant or breastfeeding?

  • Although no human studies have assessed the effects of Tobradex on the fetus, animal studies have shown adverse fetal effects. Physicians should prescribe it to women who are pregnant only if its benefits are deemed to outweigh the potential risks.
  • It is not known if Tobradex is excreted into breast milk.

What else should you know about tobramycin and dexamethasone?

What preparations of tobramycin and dexamethasone are available?
  • Ophthalmic solution or ointment: 0.3% tobramycin and 0.1% dexamethasone.
  • Opthalmic Suspension: 0.3% tobramycin and 0.05% dexamethasone.
How should I keep tobramycin and dexamethasone stored?

TOBRADEX should be kept at room temperature, 15-30 C (59-86 F), and protected from direct light.


Tobramycin and dexamethasone (Tobradex, Tobradex ST) is a medication prescribed for the treatment of steroid responsive ocular inflammation that requires steroid treatment, and is caused by a bacterial infection, or if there is a risk of infection. Side effects, drug interactions, and dosage information should be reviewed prior to taking this medication.

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Medically reviewed by Eni Williams, PharmD, PhD

FDA Prescribing Information.