Ophthalmic toxicity ocular effects

Ophthalmic effects due to direct ocular exposure to OPs include optic neuropathy, retinal degeneration, defective vertical smooth pursuit, myopia, and miosis. Respiratory effects, including muscarinic, nicotinic, and central effects, contribute to respiratory distress in acute and delayed OP toxicity, Muscarinic effects, such as bronchospasm and laiyngeal spasm, can lead to airway obstruction. Nicotinic effects can lead to weakness and paralysis of respiratory oropharyngeal tiiuscles. Central effects can lead to cessation of respiration. 

The routine ophthalmic examination is an efficient and effective technique to identify ocular toxicity (Munger and Collins, 2013 Wilkie, 2014). Long a required evaluation in Good Laboratory Practice (GLP) safety studies, these examinations can be readily applied to any mammalian in vivo study in which ocular effects are anticipated or observed. Minimal pharmacologic intervention is required to examine the eye, and most typical laboratory animal species require only manual restraint. The examinations are not invasive, and the same animal or cohort of animals can be examined... 

This preservative is comparatively new to ophthalmic preparations and is a polymeric quaternary ammonium germicide. Its advantage over other quaternary ammonium seems to be its inability to penetrate ocular tissues, especially the cornea. It has been used at concentrations of 0.001-0.01% in contact lens solutions as well as dry eye products. At clinically effective levels of preservative, POLYQUAD is approximately 10 times less toxic than benzalkonium chloride [87,137], Various in vitro tests and in vivo evaluations substantiate the safety of this compound [137,141,142], This preservative has been extremely useful for soft contact lens solutions because it has the least propensity to adsorb onto or absorb into these lenses, and it has a practically nonexistent potential for sensitization. Its ad-sorption/absorption with high water and high ionic lenses can be resolved by carefully balancing formulation components [143],... 

Surfactants. The use of surfactants is greatly restricted in formulating ophthalmic solutions. The order of surfactant toxicity is anionic > cationic >> nonionic. Several nonionic surfactants are used in relatively low concentrations to aid in dispersing steroids in suspensions and to achieve or to improve solution clarity. Those principally used are the sorbitan ether esters of oleic acid (Polysorbate or Tween 20 and 80), polymers of oxyethylated octyl phenol (Tyloxapol), and polyoxyl 40 stearate. The lowest concentration possible is used to perform the desired function. Their effect on preservative efficacy and their possible binding by macromolecules must be taken into account, as well as their effect on ocular irritation. The use of surfactants as cosolvents for an ophthalmic solution of chloramphenicol has been described [271]. This com-... 

Miconazole Topical 1% ophthalmic suspension 1 drop qlh Subconjunctival 10 mg/0.5 ml Topical side effects of burning, itching, tearing Not commercially available both topical and subconjunctival formulations must be compounded fV brand discontinued in United States Good ocular penetration with topical and subconjunctival use Toxic conjunctival necrosis may occur with subconjunctival use Pregnancy category C lactation safety unknown... 

Itraconazole is a broad-spectrum synthetic triazole that has good oral bioavailability and is less toxic than amphotericin B and ketoconazole.The solution has better bioavailability than the capsule and provides higher plasma concentration levels. Compared with fluconazole and ketoconazole, itraconazole penetrates all ocular tissues poorly when orally administered. Itraconazole can be used as a 1% ophthalmic suspension but is not very effective in treating severe fungal keratitis. 

Prolonged therapy can cause a number of adverse reactions in the eyes. Trivial effects are ocular discomfort, conjunctival pain, and increased ocular tension, but mydriasis, photophobia, blurred vision, diplopia, amblyopia, and loss of vision can occur. The most serious complications are retinopathy with reduced retinal sensitivity, and corneal and retinal pigmentation. They are reversible, but improvement is slow. A report on indometacin retinopathy has added more doubt than certainty to the question of the frequency and severity of retinal toxicity (SEDA-14, 93). Patients taking prolonged therapy should have regular ophthalmic examinations. 

Sulfacetamide is the IV-acetyl derivative of sulfanilamide. The sodium salt of sulfacetamide, because of its effectiveness and low toxicity, continues to be the most widely prescribed sulfonamide in the form of eye-drops and ointment for ophthalmic infections. It was introduced in Europe as "Albucid" in 1938 for various eye and other topical infections. Since its use in the treatment of corneal ulcers (1), sulfacetamide is still popular in ophthalmology. The sodium salt is highly soluble at the physiologic pH of 7.4, and is especially suited, as a 10-30% solution, for repeated topical application in the local management of ophthalmic infections (2-4). It is used mainly in the treatment of acute conjunctivitis and in the prophylaxis of ocular infections after injuries or burns (5). Several reviews on various aspects of sulfacetamide have been published (6-10). 

Ophthalmic diseases are most commonly treated by topical instillation of eye drops. These formulations evidence limitations like poor stability and efficacy, reduced cor-neal/scleral permeability, systemic toxicity and lack of compUance [2]. In this sense, the development of effective therapies for visual disorders is of high priority [1], which makes the field of ocular delivery one of the most interesting and challenging areas for pharmaceutical scientists [3]. There has been significant research directed towards the development of new systems for controlled drug delivery in ophthalmology such... 

Ocular toxicity and systemic adverse effects of 0.3% ofloxacin ophthalmic solution (0.3%OFLX) which was administered 3 times daily for one year were studied in dogs. 

It is concluded from these results that one year application of 0.3%OFLX ophthalmic solution to dogs causes neither ocular toxicity nor systemic adverse effect. 

In the present study, we examined ocular toxicity of ofloxacin ophthalmic solution (3 times daily for one year application) in beagle dogs with pigmented eyes. In order to investigate the effects of melanin-bound ofloxacin on retinal function and the effect of ofloxacin on central nerve system, electroretinogram (ERG) was recorded and behavior of dogs was observed during test periods. 

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