Ophthalmic drugs

Advancing Ophthalmic Drug Therapy, InSite Vision company promotional pubHcation, Alameda, Calif., 1989. 

Some ophthalmic drugs produce blurring of vision, which can result in falls and other injuries. The nurse warns patients to exercise care when getting out of bed when the vision is impaired by these drugp. Patients using the pilocarpine ocular therapeutic system must have the system replaced every 7 days (see Chap. 24). The system is inserted at bedtime because myopia (nearsightedness) occurs for several hours after insertion. 

Older adults, in particular, are at risk for exacerbation of existing disorders such as hypertension, tachycardia, or arrhythmias if systemic absorption of sympathomimetic ophthalmic drugs occurs... 

If more than one topical ophthalmic drug is being used, administer the dragp at least 5 to 10 minutes apart or as directed by die physician. 

A number of articles considered the association of chitosan with polylactic acid or similar compounds [47-49] another group of articles presented new data on highly cationic chitosans [ 50 - 55]. More data have also been made available on the delivery of growth factors [56] and ophthalmic drugs [57,58], on the activation of the complement, macrophages [59-61] and fibroblasts [62], on mucoadhesion [63] and functionalization of chitin [64]. The development of new carriers for the delivery of drugs, and the interactions of chitosans with living tissues seem therefore to be major topics in the current research on chitosan. Therefore, this chapter will place emphasis on these aspects. 

Singh, K., and Mezei, M. (1983). Liposomal ophthalmic drug delivery system. I. Triamcinolon acetonide, Int. J. Pharm., 16,... 

Wait at least 5 minutes before instilling another ophthalmic drug preparation. 

S Ding. Recent developments in ophthalmic drug delivery. Pharm Sci Tech Today 1(8) 328 335, 1998. 

The significance of the barrier function of membranes has been the topic of considerable research. The blood-brain barrier and the blood-retinal barrier are well understood, and the microscopic structures imparting and controlling barrier properties have been quite thoroughly investigated and the science reviewed [15, 154-155], The structures and functions of ocular membranes specific to transport associated with ophthalmic drug administration also have been topics of extensive research [15, 157-158],... 

Finally, from the available research into the variety of mechanisms for targetting ophthalmic drugs to specific tissues, means for integrating—both figuratively and literally—combinations of effects are now available [15]. Certainly, the combination of hydrodynamics, retention or sustained release, and diffusional or even active transport can be computed, their influence anticipated, and some specific deficiencies addressed. Nonetheless, many unanticipated interactions may often intrude and still leave the field heavily dependent on empirical assessment. 

It is quite rare that the composition or the packaging of an ophthalmic pharmaceutical will lend itself to terminal sterilization, the simplest form of manufacture of sterile products. Only a few ophthalmic drugs formulated in simple aqueous vehicles are stable to normal autoclaving temperatures and times (121°C for 20-30 min). Such heat-resistant drugs may be packaged in glass or other heat-de-formation-resistant packaging and thus can be sterilized in this manner. The convenience of plastic... 

J. R. Robinson, ed. Ophthalmic Drug Delivery Systems, Academy of Pharmaceutical Sciences, American Pharmaceutical Association, Washington, DC, 1980. 

Ophthalmic Drug Delivery Systems, edited by Ashim K. Mitra... 

I Ahmed, TF Patton. (1985). Importance of the noncorneal absorption route in topical ophthalmic drug delivery. Invest Ophthalmol Vis Sci 26 584-587. 

SD Alani. (1990). The ophthalmic rod—A new ophthalmic drug delivery system. I. Graefes Arch Clin Exp Ophthalmol 228 297-301. 

VHL Lee. (1993). Precorneal, corneal, and postcorneal factors. In AK Mitra, ed. Ophthalmic Drug Delivery Systems. New York Marcel Dekker, pp 59-81. 

SS Chrai, MC Makoid, SP Eriksen, JR Robinson. (1974). Drop size and initial dosing frequency problems of topically applied ophthalmic drugs. J Pharm Sci 63 333-338. 

Operations improvement, waste minimization via, 25 884t Ophthalmic drug delivery systems, 18 711 Ophthalmic drug dosage forms, 18 716 Ophthalmic solutions, ethylene oxide polymers in, 10 687 Opiates, economic aspects, 2 108 Opium, 2 89-90... 

Patrick Faustino Division of Anti-Inflammatory, Analgesic and Ophthalmic Drug Products, FDA, R 310,9021 Corporate Boulevard, Rockville, Maryland 2085, USA... 

Mitra AK. Ophthalmic drug dehvery devices. In Tyle P, ed. Drug Delivery Devices. Fundamentals and Applications. New York Marcel Dekker, 1988 455-70. 

General considerations in topical ophthalmic drug therapy Proper administration is essential to optimal therapeutic response. In many instances, health professionals may be too casual when instructing patients on proper use of ophthalmics. The administration technique used often determines drug safety and efficacy. 

Ophthalmic ointments may impede delivery of other ophthalmic drugs to the affected side by serving as a barrier to contact. 

Topical application is the most common route of administration for ophthalmic drugs. Advantages include convenience, simplicity, noninvasive nature, and the ability of the patient to self-administer. Because of blood and aqueous losses of drug, topical medications typically do not penetrate in useful concentrations to posterior ocular structures and therefore are of no therapeutic benefit for diseases of the retina, optic nerve, and other posterior segment structures. 

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