CLINICAL PHARMACOLOGY
Corticoids suppress the inflammatory response to a variety of agents and they probably delay or slow healing. Since corticoids may inhibit the body’s defense mechanism against infection, a concomitant antimicrobial drug may be used when this inhibition is considered to be clinically significant. Clinical studies have demonstrated that Fluorometholone Acetate Suspension is a potent corticosteroid.
In clinical studies of documented steroid-responders, fluorometholone acetate demonstrated a significantly longer average time to produce a rise in intraocular pressure than dexamethasone phosphate; however, in a small percentage of individuals, a significant rise in intraocular pressure occurred within one week. The ultimate magnitude of the rise was equivalent for both drugs.
The antibiotic component in the combination (tobramycin) is included to provide action against susceptible organisms. In vitro studies have demonstrated that tobramycin is active against susceptible strains of the following microorganisms: Staphylococci, including S. aureus and S. epidermidis (coagulase-positive and coagulase-negative), including penicillin-resistant strains.
Streptococci, including some of the Group A 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 strains, Haemophilus influenzae and H. aegyptius, Moraxella lacunata, and Acinetobacter calcoaceticus (Herellea vaginacola) and some Neisseria species.
Bacterial susceptibility studies demonstrate that in some cases microorganisms resistant to gentamicin remain susceptible to tobramycin. Bacterial resistance to tobramycin may develop upon prolonged use.
No data are available on the extent of systemic absorption from Tobraflex™ Ophthalmic Suspension; however, it is known that some systemic absorption can occur with ocularly applied drugs.
When a decision to administer both a corticoid and an antibiotic is made, the administration of such drugs in combination has the advantage of greater patient compliance and convenience, with the added assurance that the appropriate dosage of both is administered, plus assured compatibility of ingredients when both types of drug are in the same formulation and, particularly, that the correct volume of drug is delivered and retained.
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