Contact allergy following administration of eyedrops and eye ointments

Systemic side effects of eye drops: a pharmacokinetic perspective

When administering eye drops, even when completely correctly applied, several routes of absorption are possible and excess amounts can sometimes cause an unwanted systemic bioavailability of the drops when not completely absorbed into the eye. Furthermore, the concentration of active ingredients in such medicinal preparations is usually very high, so that despite the correct application of the recommended dose, considerable amounts may be absorbed in an unwanted manner through various routes. Children are subject to a much higher risk of systemic side effects because ocular dosing is not weight adjusted and physiological development (eg, liver status) differs from that of adults. There is a lack of information about pediatric dosing in the current literature. This review summarizes the most important clinically relevant systemic side effects that may occur during ophthalmic eye treatments. In this review, we discuss general pharmacokinetic considerations as well as the advantages, disadvantages, and consequences of administering drugs from some important drug groups to the eye.

Drug-induced toxic reactions in the eye: an overview

Every drug can produce untoward consequences, even when used according to standard or recommended methods of administration. Adverse drug reactions can involve every organ and system of the body, even the eye, and frequently are mistaken for signs of underlying disease. Reactions in the eye may involve the eyelids, periorbital tissues, lacrimal apparatus, conjunctiva, cornea, lens, iris, ciliary body, intraocular pressure, retina, optic nerve, and ocular movement. In addition, fetal abnormalities can be caused by the use of eye drugs during pregnancy. Topical ophthalmic therapies or the use of ophthalmic dyes may cause systemic reactions. This article reviews drugs used systemically or topically that may cause adverse effects in the eye and related structures. Adverse ocular reactions to medications create an important health problem, and nursing professionals in close contact with patients inside and outside the hospital must assume a role in detecting them early, identifying them, educating the patient about them, and treating them.

An in vitro analysis of aminoglycoside corneal epithelial toxicity

We evaluated the cytotoxicity of four aminoglycoside agents (neomycin, gentamicin, tobramycin, and amikacin) using an in vitro confluent rabbit corneal epithelial cell culture model. Primary corneal epithelial cell cultures were established and cells replated at 2 x 10(4) cells/2 cm2 well. After 48 hours either vehicle or an antibiotic was added at varying concentrations, each for 5, 30, or 60 minutes. 3H-thymidine was added immediately after drug removal and incorporation was measured 8 hours after drug or vehicle exposure. Comparisons of each drug to vehicle were expressed as % inhibition of control culture values. At the 5-minute exposure time tobramycin and amikacin showed no significant inhibition at any concentration, whereas neomycin and gentamicin showed significant inhibition at 6 mg/ml and 3.5 mg/ml or greater concentrations, respectively (p less than 0.05). At 30- and 60-minute exposure times all agents demonstrated significant inhibition at all tested concentrations in a non-dose dependent fashion (p less than 0.05). These in vitro data corroborate the animal and limited clinical data available for the aminoglycosides. Based on these toxicity profiles, tobramycin appears to be the topical agent of choice in the treatment of susceptible bacterial keratitis.

Contact allergy to components in topical ophthalmologic preparations

Contact allergy to various components of topical ophthalmological preparations was tested in 27 patients suffering from prolonged or chronic conjunctivitis, keratoconjunctivitis or blepharoconjunctivitis. Our results reveal relevant allergy towards ophthalmological preparations in 44.4% of patients tested. Allergic reactions to topical antibiotics, especially to neomycin (18.5%) and bacitracin (7.4%) was encountered as well as allergy to preservatives such as benzalconium chloride (3.7%). It is essential to bear in mind that contact allergy to components of topical preparations may cause complications and prolongation of symptoms during treatment, and therefore the importance of performing patch tests in prolonged cases of conjunctivitis or keratoconjunctivitis is stressed.