COMPATIBILITY OF CORTICOSTEROIDS AND ANTIBIOTICS IN COMBINATION

Purpose: To study the compatibility of combinations of antibiotics and steroids commonly used in anterior segment surgery. Setting: Research Laboratory, Helsinki University, Finland. Methods: Aggregate producti on in vitro and in vivo was studied for three injectable antibiotics ( cefotaxime sodium, tobramycin sulfate, and gentamicin) and four cortic osteroids (triamcinolone acetonide, methylprednisolone sodium succinat e, methylprednisolone acetate, and dexamethasone sodium phosphate) usi ng conventional and dark-field microscopy. Aggregate formation on coll agen shields and subconjunctival aggregate formation of tobramycin sul fate in combination with methylprednisolone acetate or dexamethasone s odium phosphate was also studied. Results: Dexamethasone sodium phosph ate (4 mg/mL) did not form aggregates with any of the three antibiotic s tested. Cefotaxime sodium did not cause aggregates when 24 mg/mL of dexamethasone sodium phosphate was used both in vitro and in vivo or i n association with collagen shields. Conclusions: To avoid undesired s ide effects, such as epithelial sloughing and corneal edema after coll agen shield application, antibiotics and steroids must be carefully se lected.