Corneal toxicity

D. Maurice and T. Singh, A permeability test for acute corneal toxicity, Toxicol. Lett., 31, 125 (1986). 

Four patients treated with latanoprost developed dendri-tiform epitheliopathy, a sign of corneal toxicity the... 

Sudesh S, Cohen EJ, Rapuano CJ, Wilson RP. Corneal toxicity associated with latanoprost. Arch Ophthalmol 1999 117(4) 539-40. 

Dart J (2003) Corneal toxicity the epithelium and stroma in iatrogenic and factitious disease. Eye 17 886-892 Wilhelmus KD (2001) The Draize Test. Surv Ophthalmol 45 493-515... 

When evaluating an acute injmy of the cornea, the practitioner is sometimes tempted to prescribe a topical anesthetic for administration at home by the patient for relief of ocular pain. This practice is extremely dangerous, however, and in numerous instances has led to severe infiltrative keratitis and even loss of the eye from anesthetic misuse or abuse by the patient.Topical anesthetics must be used only for the pmpose of obtaining initial relief of ocular pain and never as part of a prolonged therapeutic regimen.The potential corneal toxicity of topical anesthetics precludes their use as self-administered drugs. 

Side effects produced by topical gentamicin or tobramycin are imcommon but can include corneal and conjunctival toxicity. Punctate epithelial erosions, delayed reepithelialization, and corneal ulceration characterize this corneal toxicity, whereas chemosis, hyperemia, and necrosis characterize conjimctival toxicity. Allergic reactions to topical gentamicin occur infrequently, but approximately 50% of patients who are allergic to neomycin are also allergic to gentamicin. 

Adenoviruses also have DNA as their genetic material and are smaller than herpesviruses, with diameters of 70 to 100 nm. Adenoviruses do not have lipid envelopes and can survive on inanimate objects. Adenoviral serotypes 3, 7, 8, 19, and 37 cause conjimctivitis and epidemic keratoconjimctivitis. Currently, no antivirals are approved for ocular adenoviral infections. Studies have shown that topical cidofitvir may be effective in lowering the frequency of severe corneal opacities, but additional studies are needed to address corneal toxicity. 

Due to corneal toxicity and the availability of more effective drugs, idoxuridine is infrequently used. Idoxuridine has poor ocular bioavailability and is not effective fc>r deep stromal disease. Resistance to idoxuridine can develop during treatment. Idoxuridine is too toxic for systemic use. 

Miconazole comes in topical (1% ophthalmic suspension), subconjunctival depot (10 mg/0.5 ml), and oral (200-400 mg/day) formulations but is not commercially available now in any of these formulations. Miconazole is relatively broad spectrum and active against most yeast but has variable coverage of Aspergillus and Fusarium. Miconazole is generally well tolerated with topical and subconjunctival administration, but cases of corneal toxicity have been reported. 

Johns KJ, Head WS, O Day DM. Corneal toxicity of propamidine. Arch Ophthahnol 1988 106(l) 68-69. 

The most frequent adverse event reported with ketorolac use is transient stinging and burning after instillation of the ophthalmic solution. Rarely, allergic reactions and superficial keratitis have occurred. Although inconsistent cases of corneal toxicity have been reported with NSAIDs, prolonged use of NSAIDs in a select group of patients showed the potential for corneal melt. Because other treatment options exist for allergic eye disease, NSAIDs do not need to be used in patients with compromised corneas or those at risk for potentially serious adverse corneal reactions. 

Not only is amiodarone well-known to cause corneal toxicity (see Drugs Affecting the Cornea and Crystalline Lens, above), but it also can cause optic neuropathy. 

Fraunfelder FW. Corneal toxicity from topical ocular and systemic medications. Cornea 2006 25 1133-1138. 

Durand-Cavagna G, Delort P, Duprat P, et al. Corneal toxicity studies in rabbits and dogs with hydroxyethyl cellulose and benzalkonium chloride. Fundam Appl Toxicol 1989 13 500-508. Li J, Xu Z. Physical characterization of a chitosan-based hydrogel delivery system. ] Pharm Sci 2002 91(7) 1669-1677. 

Hyndiuk RA, Schultz RO. Overview of the corneal toxicity of surgical solutions and drugs and clinical concepts in corneal edema. Lens Eye Toxic Res 1992 9 331-350 Imkamp E, Kaden P, Kuss M, Hunold W, Mittermayer C. Konzentrationsabhangige Effekte viskochirur-gischer Substanzen auf das Zellwachstum boviner Kornea-Endothelzellen. Fortschr Ophthalmol 1988 85 434-436... 

TOPICAL FLUCONAZALE HIGH PENETRATION WITHOUT CORNEAL TOXICITY... 

Koh V, Khor WB, Lim L. Chlorpromazme-induced corneal toxicity. Arch Ophthalmol 2012 130(11) 1409. 

Pathak, M.K., Chhabra, G., Patheik, K. Design and development of a novel pH triggered nanoemulsified in-situ ophthalmic gel of fluconazole ex-vivo transcomeal permeation, corneal toxicity and irritation testing. Drug. Dev. Ind. Pharm. 39(5), 780-790 (2013)... 

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