Abstract
Purpose:
Currently high concentration ophthalmic antibiotics were introduced to increase the pharmacokinetic properties. However toxicity is a concern in using these agents. This study evaluated the cytotoxicities of various antibiotic eyedrops on SV40-immortalized human corneal epithelial cells by using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay.
Methods:
Tested drugs were Cravit (levofloxacin 0.5%), Cravit 1.5 (levofloxacin 1.5%), Quixin (levofloxacin 0.5%, Benzalkonium chloride (BAK) 0.005%), Iquix (levofloxacin 1.5%), Vigamox (moxifloxacin 0.5%), Moxeza (moxifloxacin 0.5%, xanthan gum), Gatiflo (gatifloxacin 0.3%), Zymaxid (gatifloxacin 0.5%, BAK 0.005%), Besivance (besifloxacin, BAK 0.01%, durasite), Azasite (azithromycin 1%, BAK 0.003%, durasite), Tobrex (tobramycin 0.3%, BAK 0.01%) and standard powders of each drug. MTS assay was performed after 5~120 minutes of exposure to each solution.
Results:
After the exposure to undiluted solutions cell viabilities were decreased to 9~73% from 5 minutes. At 30 minutes tobrex, zymaxid and quixin showed marked toxicity, Cravit 1.5, Iqux and Vigamox showed moderate toxicity and Cravit and Gatiflo showed mild toxicity. When exposed to 10 times diluted solutions, Tobrex, Besivance, Zymaxid, Quixin and Azasite, BAK containing products, showed moderate toxicity. After the exposure to standard powder, 0.6% besifloxacin, 0.5% gatifloxacin, 0.5% moxifloxacin, 1.5% levofloxacin and 0.5% levofloxacin showed toxicity results with decreased order. However 1% azithromycin and 0.3% tobramycin showed almost negative cytotoxicity.
Conclusions:
High concentration drugs didn’t show increased cytotoxicity. The most important factor for the determination of cytotoxicity of antibiotic solutions was the concentration of BAK.
Keywords: 422 antibiotics/antifungals/antiparasitics •
573 keratitis •
513 endophthalmitis