Ophthalmic Solutions

Purpose. Gentamicin eye drop solutions have a short precorneal residence time. The present study investigates the effect of gentamicin using a new long acting delivery Bioadhesive Ophthalmic Insert (BODI) in healthy dogs and rabbits and compares the results with a conventional regimen using an eye drop solution.

The purpose of this study was to examine the feasibility of using irreversible electroporation (IRE) as a non-chemical method for eliminating microorganisms of liquid drugs. The studied drug was a topical ophthalmic medication, a pharmaceutical field in which the problem of microbial contamination has not yet been adequately solved, especially in the case of eye drops prescribed for chronic use. Commercially available Hylo-Comod® preservative-free eye drop solution was subjected to contamination with Escherichia coli bacteria (106 colony forming units/mL). Electroporation parameters for bacterial control were investigated by comparing the effects of electrical fields of 5.4, 7.2, and 10 kV/cm, delivered as 100-µs square pulses at 1 Hz in sequences of 10 pulses, 20 pulses, or 20 pulses delivered as four sets of five pulses with 1-min intervals between each set. Microorganism survival after treatment was determined by pour plate counting. Effects of the treatment parameters on temperature and pH were recorded. Bacterial survival was lowest (0.14% ± 0.03%) after application of 20 pulses delivered as four separate sets. With that application mode, the solution remained at pH 7.5 and the temperature rose to 35.6° ± 0.2°C. Because IRE can be efficiently delivered under conditions that avoid the potentially deleterious effects of electrical pulses on temperature and pH, it appears to be a feasible method for bacterial control of drugs in solution. The principles established in this study can be applied to any drug in solution and optimized individually according to the solution's composition.

This Phase 2 clinical trial assessed the efficacy and safety of the novel antioxidative, renewable compound SkQ1 for topical treatment of dry eye signs and symptoms. In a single-center, randomized, double-masked, placebo-controlled, 29-day study, 91 subjects with mild to moderate dry eye instilled the study drug twice daily and recorded dry eye symptoms daily. Subjects were randomized 1:1:1 into one of three ophthalmic solution treatment groups: SkQ1 1.55 µg/mL, SkQ1 0.155 µg/mL, or 0.0 µg/mL (placebo). Subjects were exposed to a controlled adverse environment chamber at 3 of the 4 study visits (Day -7, Day 1, and Day 29). Investigator assessments occurred at all study visits. SkQ1 was safe and efficacious in treating dry eye signs and symptoms. Statistically significant improvements with SkQ1 compared to placebo occurred for the dry eye signs of corneal fluorescein staining and lissamine green staining in the central region and lid margin redness, and for the dry eye symptoms of oc...

Niosomes has gained tremendous popularity as ultimate drug carrier. Lot of research work is being carried out on preparation of niosomes for ophthalmic use having no significant effect on vision and its sustained release pattern. Chloramphenicol niosomes were prepared using two different ratios of cholesterol, drug and surfactant, termed as EIN-1, EIN-2 by ether injection method and their entrapment efficiency, particle size. The in vitro drug release pattern was observed for ten hours. The EIN-2 showed 90% entrapment and released 81% of entrapped drug after 10 hours. Zeta potential & viscosity were determined and in-vivo comparison was made with Chloramphenicol eye drops where it exhibited Cmax of 15 μ g/ml. Stability studies were done to determine shelf life. MIC of selected strain of S. aureus was also determined. EIN 2 niosomal suspension was compared with Chloramphenicol eye drops in experimental conjunctivitis in albino rabbits. In-vitro studies are encouraging as niosomes released about 75% of total entrapped drug by EIN-1 and 81% of total entrapped drug by EIN 2. In vivo study shows that niosomes released the drug in eye in acceptable range and showed a sustained release pattern without affecting the vision. Niosomes were found ultimate ophthalmic drug carriers capable to release drug in sustained and determined pattern.

Purpose: To describe the outcome of a series of Acanthamoeba keratitis treated with a similar regimen. Meth-ods: All cases diagnosed with Acanthamoeba keratitis in a referral centre from June 1994 through June 1997 were included. Diagnosis of Acanthamoeba keratitis was ...

Bilateral angle closure glaucoma is a rare ocular emergency which can be a potentially blinding condition. A case of 72 years male, who developed headache and vomiting after five days of demise of his mother followed by blurring of vision. He was taken to the general hospital where all the routine tests and CT Scan head failed to reveal the cause. After two days of admission, patient was referred for ophthalmic consultation. On ocular examination he was diagnosed as a case of bilateral angle closure glaucoma. After two hours of treatment patient was comfortable with normal intraocular pressure and reasonably good vision.

In the present study, viscous solutions of cysteamine hydrochloride (CH) were prepared by using 0.5%, 1.0%, 1.5% or 3.0% of hydroxypropylmethylcellulose (HPMC) and were evaluated for their in-vitro characteristics and stability. Osmolalities, pH and viscosity of the formulations were determined. The influence of benzalkonium chloride and autoclave sterilization on solution characteristics was also investigated. For stability assessment, the viscous solutions were stored at +4 and +25 °C over 12 months. In-vitro characteristics and CH contents of the stored solutions were monitored. Irritation tests for the formulations were evaluated on rabbit eyes. Dialysis sac technique was used to perform in vitro release study of the solutions containing 1.0% and 1.5% HPMC. All of the viscous solutions tested showed non-newtonian (dilatant) flow behavior. Osmolality values were ranked between 351.2 ± 6.2 and 355.1 ± 7.9 mOsm kg−1, and pH values were between 3.97 ± 0.1 and 3.98 ± 0.2 for all the solutions. Furthermore, no significant changes in dilatant behavior, osmolality or pH values of the pure HPMC solutions were observed. After addition of the excipients or CH-excipients, increased viscosity values were noted in these formulations. Neither benzalkonium chloride nor autoclave sterilization had any influence on viscosity, pH or osmolality values of the solution containing 1.5% HPMC. Stability studies showed that a faster decrease in the concentration of CH was observed in the formulations stored at 25 °C compared to those kept at 4 °C; no changes were determined in osmolality values of the solutions at all storage conditions. Increased pH and decreased viscosity values were noted in HPMC solutions containing CH and excipients, while no changes in these values were observed for pure HPMC solutions kept at 4 and 25 °C. In vitro release tests revealed that 81.2% and 85.3% of CH were released from the viscous solutions containing 1.5% and 1% HPMC, respectively, in 8 h. No irritation was observed when the viscous solutions were tested on rabbit and human eyes.

High myopia is a major cause of uncorrectable visual impairment. It imposes major challenges and costs for refractive correction, and for the treatment of associated pathological complications. In the last 60 years, there has been a marked increase in the prevalence of high myopia in younger generations in developed countries in East and Southeast Asia, and there are signs of similar, but less pronounced increases in North America and Europe. In some parts of the world, 70-90% of children completing high schools are now myopic, and as many as 20% may be highly myopic. It is now clear that myopia results from excessive axial elongation of the eye, and this greater rate of axial elongation appears to be environmentally driven. Experimental studies have examined the biochemical mechanisms involved in regulation of axial elongation; and, from these studies, some options have emerged for preventing the development of myopia or slowing myopia progression. Atropine eye drops have been quit...

To investigate if postoperative treatment with dexamethasone eye drops has the capacity to affect longitudinal growth in newborn rabbits. Thirty-four male and female rabbits had clear lens extraction performed in one eye at 3 wk of age and were then treated either intensively (group 1) or less intensively (group 2) with de-escalating doses of dexamethasone eye drops for 8 wk (average doses 0.27 and 0.10 mg/kg body weight/day, respectively). The control group (group 3) received vehicle eye drops only. Body weight and crown-rump length were recorded every week. After 8 wk of treatment, all rabbits were killed and the left femur was measured. Rabbits treated with dexamethasone eye drops gained weight slower (711+/-42 and 989+/-153 g weight increase for groups 1 and 2, respectively) than control animals (group 3; 1224+/-87 g weight increase; p<0.001 vs group 1, p<0.01 vs group 2). Longitudinal growth, determined as increase in crown-rump and femur lengths, was impaired by dexamethasone eye drops in a dose-dependent way. Crown-rump length increased by 8.25+/-0.86, 10.90+/-1.19 and 15.35+/-1.31 cm in groups 1, 2 and 3, respectively (p<0.001 for all comparisons). At endpoint, i.e. after 8 wk of treatment, the average femur length was 6.36+/-0.21, 7.39+/-0.27 and 8.37+/-0.28 cm in groups 1, 2 and 3, respectively (p<0.001 for all comparisons). Dexamethasone, administered topically as eye drops, has systemic effects and impairs longitudinal growth in young rabbits. Therefore, we propose that growth should be closely monitored in all children intensively treated with glucocorticoid eye drops.

Formulation of a new Prednisolone acetate (1%) ophthalmic suspension to obtain a better contactibility of the drug at the site of action. The formulation was evaluated and optimized based on physiological, physicochemical and pharmaceutical parameters and prepared aseptically, keeping particle size between 1-3 microm, while viscosity enhancer, preservative, chelating agent were used to increase the transient residence time, antimicrobial preservation respectively. Isotonicity of the formulation was maintained. Buffering agents used were having buffering capacity NMT 0.05%. pH adjusted at which Prednisolone acetate was stable. The finished product subjected to stress conditions to check the physical stability of the formulation. The formulation was packed in LDPE plastic vials, and subjected to accelerated stability studies at 40 degrees C and the kinetic and predictive method was employed for the determination of degradation rate constant and shelf life. The results showed that the ...

Dry eye is the most common reason for contact lens (CL) discontinuation, and the patient with pre-existing dry eye presents particular challenges to the CL fitter. Poor tear film quality/stability, oxygen deprivation, lens deposits, and adverse reactions to CL solutions all contribute to dry eye, and lid disease, allergies, environmental factors, and medications can further hamper successful CL wear by the patient with dry eye. Health and comfort of the ocular surface is affected by the water content, ionicity, oxygen permeability, and modulus of elasticity of the lens, as well as by surface characteristics, such as protein, lipid, and mucin deposition; protein adsorption; and wettability. The choice of CL cleaning solutions with regard to action, cytotoxicity, and biocompatibility are as important as the choice of the CL itself. With appropriate management of the lid, meibomian gland, and ocular surface conditions that produce dry eye, careful selection of lenses and solutions, and vigilant follow-up, successful CL wear should be achievable for the dry eye patient.