Unless the situation mandates the use of a fourth generation fluoroquinolone as an adjunct to a steroid, TobraDex remains the "go-to" drug for our profession.

Efficacy and safety

TobraDex, a tobramycin/dexamethasone combination, has a well-accepted effective aminoglycoside that addresses the

typical bacteria that we encounter in eyelid disease and the other entities for which I would use this drug. Tobramycin is most effective against gram-negative bacteria, especially Pseudomonas, but it is also effective against most gram-positive bacteria.

For short-term use, this drug is an excellent cost-effective choice for killing bacterial ocular pathogens, in combination with its steroid counterpart. Rarely is it used long enough to produce any significant side effects, unless the patient is pre-sensitized. Although a fourth generation antibiotic/steroid combo might be a good alternative, none are marketed to date.

The steroid is usually the main component that I am interested in when prescribing TobraDex. Poorly controlled inflammation may lead to significant ocular damage, so my goal in using a combination drug is to knock-out inflammation. Two recent studies, presented at ARVO 2005, prove the efficacy of dexamethasone. The first concluded that dexamethasone was more effective than loteprednol at reducing neutrophil release, a key component of the inflammatory cascade. The other found that tobramycin/dexamethasone significantly decreased the clinical signs of inflammation when compared with tobramycin/loteprednol.

Similarly, tobramycin/dexamethasone demonstrated clinically and statistically significant improvements in the total ocular surface scores when compared with tobramycin/loteprednol. Having appreciated excellent patient responses to TobraDex and its history of documented efficacy, this proven drug is a "no-brainer" to prescribe in my practice. Considering that I use steroid combination drugs for short-term treatment, my concern about steroid responder issues is minimal and certainly not a reason to use a different steroid. It's well-documented that it can take three to five weeks before a steroid responder will demonstrate a rise in IOP, well after the duration of therapy when I prescribe TobraDex.

Another consideration is availability. Most third party carriers cover TobraDex. Every time I prescribe a drug that is not on the patient's formulary, I spend time on the phone with the patient, pharmacy and/or carrier. It is time poorly spent. TobraDex is also safe and approved down to two years of age and conveniently available in both ointment and drop formulations.

Time-tested formula

We have had the luxury of transitioning from the days of Blephamide to the "Gold Standard" of TobraDex. A time-tested and proven formulation, it is my first choice when selecting a combination drug for my patients. I see no scientific evidence to dispute its success or a compelling reason to jump ship.  If the diagnosis is appropriate to treat with a combination antibiotic/steroid, TobraDex should be your drug of choice.

Dr. Corbin is in private group practice. He serves on the Adjunct Faculty at Pennsylvania College of Optometry and lectures nationally.