Eye drugs

D Risk for Ineffective Regimen Management related to lack of knowledge of technique of instilling an eye drug... 

Barbizhayev, M. A., Deyev, A. I., Yermanova, V. N., Brikman, I. V., and Bours, J. (2004). Lipid peroxidation and cataracts N-acetylcamosine as a therapeutic tool to manage age-related cataracts in human and canine eyes. Drugs 5,125-139. 

C. Lead can substitute for calcium in the bone crystal lattice, resulting in bone brittleness. Bone may become a reservoir for other substances as well. Several drugs, such as chlorpromazine, may accumulate in the eye. Drugs with extremely high Upid-water partition coefficients tend to accumulate in fat, while basic amines tend to accumulate in the lungs. Many agents bind avidly to albumin in the blood. 

PUtz-Seymour J, Jampel H. The one-eye drug trial revisited. Ophthalmology 2004 111 419-420. 

Idoxuridine, which is active against Herpes simplex and Varicella zoster, has only been used in topical antiherpetic solutions. Idoxuridine has been used to treat superficial keratitis, but with poor results in deep stromal diseases because of poor solubility. However, idoxuridine is unstable and cannot eliminate the virus from the eye. Drug allergy and toxicity occur in 5-8% of patients. 

Topical tretinoin has also been used as an ophthalmic ointment 0.01% in the treatment of squamous metaplasia associated with dry eyes. In 161 patients with either keratoconjunctivitis sicca or conjunctival cicatricial diseases (Stevens-Johnson syndrome, inactive pemphigoid, radiation-induced dry eye, drug-induced pseudopemphigoid, and toxic epidermal necrolysis) there were no beneficial effects in the former, but significant reversal of conjunctival kerati-nization in the temporal bulbar site in the latter (1). Adverse effects were hmited to blepharoconjunctivitis and resolved on withdrawal. 

Even in the inflamed eye, drug levels achieved in the anterior segment following parenteral administration alone using routine dosages are likely to be lower than those achieved by combined topical and subconjunctival administration. However, parenteral medication in combination with subconjunctival injection is necessary to achieve therapeutic levels of drug in the chorioretina. 

Figure 1.1 shows the active site of the enzyme human carbonic anhydrase II. Carbonic anhydrases convert carbon dioxide into hydrogen carbonate ion (HC03 ). In the eye this is a critical step in the secretion of aqueous humour (the fluid that fills the eye). Drugs that inhibit this enzyme (e.g. timolol) have been used to treat glaucoma by reducing the secretion. 

Sedlacek, J. Possibilities of application of eye drugs with the aid of gel contact lenses. Cesk. Oftalmol. 1965, 27, 509-512. 

Grant WM (1974) Toxicology of the Eye Drugs, Chemicals, Plants, Venoms, 2nd Ed. Thomas, Springfield, IL, pp 339-340. 

Jain GK, Warsi MH, Nirmal J et al (2012) Therapeutic stratagems for vascular degenerative disorders of the posterior eye. Drug Discov Today 17 748-59... 

D. Jain, E. Carvalho, A.K. Banthia, and R. Banerjee, Development of polyvinyl alcohol-gelatin membranes for cuitibiotic dehvery in the eye. Drug Dev Ind Pharm, 37,167-177,2011. 

Uses Thickener and gelling agent esp. effective pH 6-8.5 improves texture and feel of formulated skin prods. primary emulsifier for multiphase emulsions of oil and water rec. for controlled-release skin or eye drug formulations Properties Off-wh. to straw-colored powd. odorless swells but does not dissolve in water sp.gr. 0.7-0.8 dec. before melting dec. before flash > 150 C 100% cone. 

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