Force requirements in topical medicine use--the squeezability factor

Squeezability of eye drop containers used in dry eye disease management

CLINICAL RELEVANCE

Ocular lubricants are the mainstay of dry eye management and are available in a variety of formulations and bottle designs. The squeezability of ocular lubricant bottles may influence administration and compliance.

BACKGROUND

A key component for managing dry eye disease is the use of ocular lubricants. The different bottle types, each with their unique material strength and dispensing mechanism, may be challenging for patients with limited hand and pinch strength. The aim of this study was to evaluate the force required to expulse a drop from different eye drop containers used in the management of dry eye disease.

METHODS

The force, in newtons (N), required to expulse a drop from different eye drops was evaluated five times using a force gauge, and divided by bottle type, i.e. tubes, unidose, multidose with preservatives, and multidose preservative free (MDPF) bottles.

RESULTS

Sixty (n = 60) bottles were examined with 57 eye lubricants and 3 dry eye medications (cyclosporine (0.5% and 0.9%), and lifitegrast). The average force varied depending on the bottle type (tubes 4.28 ± 1.29 N; unidose 14.24 ± 4.83 N; multidose 16.62 ± 5.21 N; MDPF 26.68 ± 8.32 N, p < 0.001). Post-hoc test revealed that MDPF bottles required more force than all other bottle types (p < 0.001), and among those, the ophthalmic squeeze dispenser bottle required significantly more force (p < 0.001). Lifitegrast required more force (17.38 ± 2.13 N) than cyclosporine 0.5% (9.16 ± 0.80 N, p < 0.024) and cyclosporine 0.9% (5.68 ± 0.40 N, p < 0.001), but was not significantly different from unidose ocular lubricants (p > 0.05).

CONCLUSION

The squeezability of bottles used in dry eye disease management varies with bottle type. Hand and pinch strength should be considered when choosing products for dry eye disease management, as the squeezability of an ophthalmic drop can influence its administration and compliance.

Eyedrop Instillation Techniques, Difficulties, and Currently Available Solutions: A Literature Review

Purpose

To review current eyedrop instillation techniques, common difficulties faced by patients instilling eyedrops, available eyedrop assistive devices, and patient education regarding eyedrop instillation.

Methods

PubMed, Embase, and Google Scholar were searched from conception until June 2022 for articles on eyedrop instillation difficulties, techniques, tools, and patient education.

Results

Instillation involves pulling down the lower eyelids and placing drops on the corneal surface or conjunctival fornix, followed by closing of the eyelids for about 1 min. Examples of techniques include eyelid closure and nasolacrimal obstruction techniques. Patients encounter many difficulties when administering eyedrops, including but not limited to poor visibility, squeezing the dropper bottle, aiming the bottle, and accidentally blinking. However, devices are available that assist with aim and dropper compression-force reduction in eyedrop instillation. These can be particularly useful in patient demographics with diminished manual dexterity or the ability to generate force from their fingers. Furthermore, despite patient education in eyedrop instillation not being a common practice, it has been found that adequate patient education can lead to significant improvement in eyedrop instillation technique.

Conclusions

While many factors are associated with poor eyedrop instillation technique, there are many solutions available including assistive devices and proper instillation education.

Artificial Tears: A Systematic Review

Artificial tears are the mainstay of dry eye disease management, but also have a role in corneal abrasion and wound healing, pain and inflammation management, conjunctivitis, keratitis, contact lens rewetting and removal, and foreign body removal. A systematic review of randomized controlled trials (PROSPERO registration CRD42022369619) comparing the efficacy of artificial tears in patients with dry eye to inform prescribing choices using Web of Science, PubMed and Medline databases identified 64 relevant articles. There is good evidence that artificial tears improve symptoms of dry eye disease within a month of regular use, applied about four times a day, but signs generally take several months to improve. Not all patients with dry eye disease benefit from artificial tears, so if there is no benefit over a month, alternative management should be considered. Combination formulations are more effective than single active ingredient artificial tears. Artificial tears containing polyethylene glycol are more effective than those containing carboxymethylcellulose/carmellose sodium and hydroxypropyl methylcellulose. Those classified as having evaporative dry eye disease, benefit from artificial tears with liposomes, especially of higher concentration. The data available is limited by the definition of dry eye disease applied in published studies being variable, as well as the disease severity examined and compliance with artificial tears being rarely quantified.

Highlighting the Microbial Contamination of the Dropper Tip and Cap of In-Use Eye Drops, the Associated Contributory Factors, and the Risk of Infection: A Past-30-Years Literature Review

The sterility of eye drop content is a primary concern from manufacturing until opening, as well as during handling by end users, while microbial contamination of the dropper tip and cap are often disregarded. The contamination of these sites during drug administration represents a risk of microbial transmission and ocular infection. In this review, we aim to assess microbial contamination of the dropper tip and cap of in-use eye drops, the associated contributory factors, and the risk of infection. We conducted a literature search of the MEDLINE, PubMed, and Cochrane Central databases. A total of 31 out of 1503 studies were selected. All the studies conducted in different settings that documented microbiologically contaminated in-use eye drops were included. Our review showed that microbial contamination of the dropper tip and cap of in-use eye drops ranged from 7.7 to 100% of the total contaminated tested samples. Documented contributory factors were conflicting across the literature. Studies investigating the association between eye infection and microbial contamination of the dropper tip and cap were scarce. New technologies offer a promising potential for securing the long-term sterility of eye drop content, tips, and caps, which could benefit from more research and well-defined study protocols under real-life scenarios.

Comparison of the Usability of Eye Drop Aids and the Conventional Bottle

(1) Background: Eye drops are the most common route of administration for ophthalmic medications. Administering drops can be a major hurdle for patients, potentially resulting in noncompliance and treatment failure. The purpose of this study is to compare the efficacy and safety of two different aids and the conventional bottle for eye drop instillation; (2) Methods: An interventional crossover study involving standard eye drop bottle, Opticare aid and Autodrop aid. The study included healthy subjects without a history of regular eye drop use; (3) Results: Twenty-six subjects were enrolled. Of those subjects, 96% and 92% were able to assemble the eye drop bottle into the Autodrop and the Opticare aids, respectively. Subjective assessment indicated that Autodrop was significantly easier to assemble than Opticare (95% CI: -1.6802 to -0.1659, p = 0.02). When using either aid, there was no contamination of the bottle tip, which occurred in 46% of subjects when no aid was used (p = 0.0005). Fewer drops were expelled when using the conventional bottle as compared to the aids (p = 0.05 compared to Autodrop, p = 0.1 compared to Opticare); (4) Conclusions: Autodrop and Opticare can assist patients with eye drop placement. These aids completely prevented bottle tip contamination, which was frequently observed when the conventional bottle was used alone.

Inkjet Printed Textile Force Sensitive Resistors for Wearable and Healthcare Devices

Pressure sensors for wearable healthcare devices, particularly force sensitive resistors (FSRs) are widely used to monitor physiological signals and human motions. However, current FSRs are not suitable for integration into wearable platforms. This work presents a novel technique for developing textile FSRs (TFSRs) using a combination of inkjet printing of metal-organic decomposition silver inks and heat pressing for facile integration into textiles. The insulating void by a thermoplastic polyurethane (TPU) membrane between the top and bottom textile electrodes creates an architectured piezoresistive structure. The structure functions as a simple logic switch where under a threshold pressure the electrodes make contact to create conductive paths (on-state) and without pressure return to the prior insulated condition (off-state). The TFSR can be controlled by arranging the number of layers and hole diameters of the TPU spacer to specify a wide range of activation pressures from 4.9 kPa to 7.1 MPa. For a use-case scenario in wearable healthcare technologies, the TFSR connected with a readout circuit and a mobile app shows highly stable signal acquisition from finger movement. According to the on/off state of the TFSR with LED bulbs by different weights, it can be utilized as a textile switch showing tactile feedback.

A Randomized Controlled Clinical Trial to Compare Conventional Drug Instillation to A Device Dropper Method in Medical Treatment of Glaucoma

PURPOSE

To compare and analyze the performance of a device dropper (DD) over conventional drop instillation (CDI) method on ease of administration, compliance, patient satisfaction, and intraocular pressure (IOP) control in persons with glaucoma on ocular hypotensive medications.

METHODS

We enrolled 72 individuals with primary open-angle glaucoma or ocular hypertension, on treatment with fixed combination (α agonist+β blocker) drugs for at least 6 months. These were randomized into two groups (36 in each arm). Group 1 administered the drug with a DD and Group 2 used CDI method. Recruited individuals were interviewed for subjective difficulties using a formatted questionnaire at first month follow-up and IOP change from baseline was evaluated.

RESULTS

Baseline demographic and ocular characteristics were similar in both groups. 57.1% in the conventional instillation and none in the DD had reported difficulty in using the eye drops on follow-up visit. DD group had significantly less spillage and contamination of eye surface or dropper tips, required minimal assistance, accurately targeted on first drop placement directly into the eye compared to CDI group (p-value<0.001). Mean IOP was comparable between the two groups.

CONCLUSION

DD instillation method was observed to be easier to administer, more accurate in targeting the conjunctival cul-de-sac, reduced wastage with lesser contamination compared to the CDI technique. DDs may be expected to have better compliance and effectiveness in medical management of glaucoma.

Investigation of visual and physical factors associated with inadequate instillation of eyedrops among patients with glaucoma

Purpose

The aim of this study was to investigate the frequency of eyedrop instillation failure and its related physical and visual function factors among glaucoma patients who used hypotensive eyedrops daily.

Subjects and methods

Patients with a history of self-instillation of one or more ocular hypotensive ophthalmic solutions for six or more months were enrolled. Definitions of instillation failure were eyedrop instillation other than on the eye surface; eyedrop contact with eyelashes; eyedrop bottle tip contact with the eyelashes, eye surface or ocular adnexa; or two or more drops instilled with one instillation trial. To clarify factors related to instillation failure, we used visual function tests and investigated cervical spine extension angles during instillation, pinching strength, physical ataxia (evaluated using the Scale for the Assessment and Rating of Ataxia), motor dysfunction of the upper limbs (evaluated using the Disabilities of the Arm, Shoulder and Hand questionnaire), and vision quality (evaluated using the National Eye Institute Visual Function Questionnaire 25).

Results

Of 103 total subjects, 61.2% satisfied the definition of instillation failure. Instillation of the eyedrop other than at the cul-desac (76.2%) was the most frequent reason for failure, followed by contact of the tip of the eyedrop bottle (22.2%) and instillation of the same or more than two eyedrops in a single attempt (11.1%). Advanced age, a shallow cervical spine extension angle, weak pinching strength, poor motor dysfunction of the upper limbs, the degree of ataxia, poor best-corrected visual acuity, and visual field scores were significant risk factors for instillation failure. Vision quality may have some relation to instillation failure.

Conclusion

It is highly recommended that instillation failure be routinely investigated even among patients with adequate experience using eyedrops and that correct therapies are chosen in a patient-based fashion.

The Design and Development of an Eye Drop Aid for Glaucoma Patients

Visual impairment is an important public health problem. A cataract is the most common eye disease, and surgical methods are mostly used. Unlike a cataract, glaucoma may lead to permanent loss of vision and can be treated appropriately using eye drops. In this study, the researchers aimed to create, design, and develop a device called “Eye Drop Aid of Naresuan University (EDANU).” This research employed mixed methods using an in-depth interview and questionnaire, which were conducted with a group of 10 experts to provide preliminary data for the design and a group of 20 volunteers to test the efficacy and safety of the EDANU compared with the instructions of the Xal-Ease™ eye drop administration and instructions as recommended by the Pharmacy Council of Thailand in the laboratory. It was found that the EDANU, which was designed and developed as a prototype using thermoplastic polyurethane, which is a highly flexible material, was more accurate, reliable, and safer than the Xal-Ease eye drop administration. The EDANU displayed efficient statistical significance and proved to be safe for using in the laboratory.This was a device that could help glaucoma patients and their caregivers have a better quality of life because this device was more accurate, reliable, and safer than the other two methods. However, the EDANU is still in the process of prototype development, and, in the future, it would still be necessary to study with a human clinical trial.

In situ forming and mucoadhesive ophthalmic voriconazole/HPβCD hydrogels for the treatment of fungal keratitis

Fungal keratitis is a severe infectious corneal disease. At present, no voriconazole ophthalmic formulations are approved by the FDA or EMA. This lack of therapeutic options leads to the reformulation of intravenous voriconazole preparations (VFEND®) by the hospital pharmacy departments to prepare the appropriate ophthalmic formulations (pharmacy compounding). However, the limited residence time of these formulations leads to an intensive treatment posology that may increase the occurrence of side effects. In the present study, two different hydrogels were developed and characterized in order to improve the voriconazole's ophthalmic solubility, permanence, and security. Voriconazole-cyclodextrin (HPβCD or HPɣCD) inclusion complexes in aqueous solutions were characterized by NMR and molecular modeling. Complexes were formed by encapsulation of voriconazole into the cyclodextrin's internal cavity which considerably increases its water solubility. Ocular safety was proven by ocular irritation studies. Permeability studies suggest both hydrogels have good corneal permeability. Furthermore, in vivo ocular permanence study by PET/CT showed a longer permanence time on the ocular surface (t_1/2 = 58.91 ± 13.4 min and 96.28 ± 49.11 min for VZHAH and VZISH 0.65 respectively) compared to the voriconazole control formulation (VFEND® t_1/2 = 32.27 ± 15.56 min). Results suggest these formulations are a good alternative for the treatment of fungal keratitis.

Development and Characterization of a Tacrolimus/Hydroxypropyl-β-Cyclodextrin Eye Drop

Uveitis is a vision inflammatory disorder with a high prevalence in developing countries. Currently, marketed treatments remain limited and reformulation is usually performed to obtain a tacrolimus eye drop as a therapeutic alternative in corticosteroid-refractory eye disease. The aim of this work was to develop a mucoadhesive, non-toxic and stable topical ophthalmic formulation that can be safely prepared in hospital pharmacy departments. Four different ophthalmic formulations were prepared based on the tacrolimus/hydroxypropyl-β-cyclodextrin (HPβCD) inclusion complexes’ formation. Phase solubility diagrams, Nuclear Magnetic Resonance (NMR) and molecular modeling studies showed the formation of 1:1 and 1:2 tacrolimus/HPβCD inclusion complexes, being possible to obtain a 0.02% (w/v) tacrolimus concentration by using 40% (w/v) HPβCD aqueous solutions. Formulations also showed good ophthalmic properties in terms of pH, osmolality and safety. Stability studies proved these formulations to be stable for at least 3 months in refrigeration. Ex vivo bioadhesion and in vivo ocular permanence showed good mucoadhesive properties with higher ocular permanence compared to the reference pharmacy compounding used in clinical settings (t_1/2 of 86.2 min for the eyedrop elaborated with 40% (w/v) HPβCD and Liquifilm^® versus 46.3 min for the reference formulation). Thus, these novel eye drops present high potential as a safe alternative for uveitis treatment, as well as a versatile composition to include new drugs intended for topical ophthalmic administration.

Novel Eye Drop Delivery Aid Improves Outcomes and Satisfaction

PURPOSE

To compare a nose-pivoted drop delivery device (NPDD) with traditional eye drop delivery in glaucoma subjects.

DESIGN

Repeated-measures case series.

PARTICIPANTS

Fifty glaucoma subjects (100 eyes) who reported difficulty self-administering eye drops.

METHODS

We compared eye drop delivery using a NPDD against traditional delivery techniques at baseline (baseline traditional) and after standardized teaching (post-teaching traditional). Subjects used a 1-to-10 scale (10 being easiest) to rate the ease of delivery with each technique and completed a satisfaction survey. Two graders used digital video to independently review eye drop delivery and recorded: (1) accurate placement: the eye drop reached the ocular surface; (2) no contact: no bottle tip contact against the ocular or periocular surface; and (3)number of eye drops dispensed. We defined primary success as accurate placement and no contact; secondary success as primary success with only 1 drop dispensed.

MAIN OUTCOME MEASURES

We used logistic-transformed generalized estimating equation (GEE) regression to compare technique satisfaction, accuracy, no contact, and primary and secondary success. Number of drops dispensed was compared using a Cox model.

RESULTS

Forty-seven of 50 subjects (94%) preferred the NPDD over traditional eye drop delivery. The mean score for ease of use was higher for the NPDD (8.9 ± 1.1) than baseline traditional (6.7 ± 2.1; P < 0.001) and post-teaching traditional (7.0 ± 2.0; P < 0.001). Forty-nine of 50 (98%) subjects thought the NPDD was comfortable to use and would recommend the device. The eye drop reached the ocular surface in a similar percentage of subjects (>90%) with each method. The bottle tip contacted fewer eyes with the NPDD (10 eyes) than baseline traditional (33 eyes; P < 0.001) and post-teaching traditional (25 eyes; P = 0.009). The number of drops dispensed was lower with the NPDD (1.7 ± 1.2) than baseline traditional (2.2 ± 1.6; P = 0.017) and post-teaching traditional (2.4 ± 1.8; P = 0.006). The NPDD increased primary and secondary success of eye drop delivery (86% and 54%, respectively) compared to baseline traditional (66% [P = 0.001] and 28% [P < 0.001]) and post-teaching traditional (70% [P = 0.005] and 40% [P = 0.018]).

CONCLUSIONS

Eye drop users preferred the NPDD over traditional eye drop delivery. The NPDD improved eye drop delivery success, reduced bottle tip contact, and decreased the number of eye drops wasted.

Daily Costs and Cost Effectiveness of Glaucoma Fixed Combinations in China

Background

The aim of this study was to compare the daily costs and cost effectiveness of fixed combination glaucoma drugs in China.

Methods

This study included the following fixed combination drugs: brinzolamide 1% and timolol 0.5% (Azarga; Alcon, Inc., Fort Worth, TX, USA), travoprost 0.004% and timolol 0.5% (DuoTrav; Alcon, Inc.), bimatoprost 0.03% and timolol 0.5% (Ganfort; Allergan, Inc., Dublin, Ireland), and latanoprost 0.005% and timolol 0.5% (Xalacom; Pfizer, Inc., New York, NY, USA). Five bottles of each drug were measured. The mean actual volume, mean actual number of drops, volume per drop, daily cost, yearly cost, and per mmHg reduction cost for each drug were calculated.

Results

The volumes per drop ranged from 32.61 ± 2.90 μl (DuoTrav) to 24.38 ± 0.23 μl (Ganfort). The number of usage days per bottle varied from 36 days (DuoTrav) to 61 days (Ganfort). Azarga had the lowest daily cost ($0.23) and yearly cost ($84.72), while DuoTrav had the highest daily cost ($0.79) and yearly cost ($287.02). Azarga costed $2.17-$3.30 per mmHg intraocular pressure reduction, which was lower than the other three drugs. For the prostaglandin and ß-adrenergic blocker FCs, Ganfort had the lowest daily cost ($0.35) and per mmHg reduction cost (from $3.40 to $4.04).

Conclusions

The daily costs of these drugs were significantly different, with Azarga having the lowest daily cost and best cost effectiveness. For the prostaglandin and β-adrenergic blocker fixed combinations, Ganfort was the most economical choice with its lower daily cost and per mmHg reduction cost. The results of this study could provide drug selection guidance from an economic perspective, but various factors should be considered when making a decision.

The Use of Generic Medications for Glaucoma

The use of generic medicines has grown considerably in recent years providing considerable cost savings. In England, generic items represented 11.7% of prescriptions for glaucoma and ocular hypertension in 2009, increasing to 55.2% of prescriptions in 2018. Generics can be brought to the market quickly and at low cost as manufacturers are not required to repeat animal or clinical research on active ingredients already approved for safety and efficacy. Although there is no regulatory requirement for studies comparing branded and generic eye drops, several randomised crossover studies have been performed comparing branded and generic prostaglandin analogues. While most have shown similar intraocular pressure lowering, studies are of short duration and have not evaluated visual field endpoints. Furthermore, differences in inactive ingredients, pH, viscosity, levels of particulate matter, and degradation over time have been reported. Other potential problems with generic eye drops include differences in bottle design affecting adherence, problems with supply, and the possibility that reduced revenue for innovator companies will lead to reduced investment in new drug development. This article reviews the potential advantages and disadvantages of generic antiglaucoma medications.

Noncompliance with Prescribed Eyedrop Regimens Among Patients Undergoing Cataract Surgery—Prevalence, Consequences, and Solutions

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Wide Variation of Squeezing Force and Dispensing Time Interval among Eyedropper Bottles

Purpose

We aimed to investigate squeezing force and dispensing time interval of the first and second eye drops among a variety of eyedropper bottles and to clarify associated factors within these parameters.

Methods

A total of 87 eyedropper bottles were involved in this study. We developed a squeezing force measuring system consisting of a syringe pump, digital force gauge, and custom-made test stand to measure the squeezing force and dispensing interval. The eyedropper bottle was housed in the system vertically, and measurements were repeated five times. We investigated the differences in squeezing force and dispensing interval by categories, including those that targeted ocular disease, brand or generic eyedroppers, shapes of eyedropper bottles, and the presence of a membrane filter inside the tip of the eyedropper bottle.

Results

The mean squeezing forces of the first drop and the second drops were 8.3 ± 3.0 N and 10.4 ± 3.2 N, respectively. Both squeezing forces had a wide variation of more than threefold. A mean interval between the first and second drops was 3.1 ± 1.2 sec with a maximum difference of more than sevenfold. Round shapes of eyedropper bottles and the presence of filter membranes significantly increased the squeezing force.

Conclusions

The squeezing force of eyedropper bottles was very wide, which may affect proper eye drop instillation. Unification of eyedropper bottles or developing mechanical aids may be useful for proper eye drop treatment.

Improving eye-drop administration skills of patients - A multicenter parallel-group cluster-randomized controlled trial

Background

Eye-drop administration errors occur in the majority of patients and increase the risk for treatment failure or systemic adverse events. While lacking knowledge is the principal error cause, most patients overestimate their skills and are unaware of often substantial knowledge gaps. Therefore, the impact of including motivational patient education on long-term eye-drop administration skills of patients was investigated.

Methods

This is a cluster-randomized controlled trial in German community pharmacies. Patient education in both groups comprised observation of the patient during eye-drop administration to identify individual errors, pharmaceutical counseling, and teach-back evaluation of the training. In the intervention group, motivational communication techniques were included to increase error awareness and readiness for patient education. In addition, intervention patients were trained on repeated errors until administration was performed correctly. In contrast, patients in the control group only received feedback on erroneous administration steps without another assessment and reinforced training.

Results

In total, 152 adult patients were eligible to the study and 91 patients (intervention group N = 46) agreed to participate in a 1-month, 6-month, and 12-month follow-up. Patient education significantly increased the proportion of patients correctly administering eye-drops from 6% (7 out of 56 intervention patients, 1 out of 82 control patients) at baseline to 35% (12 out of 30 intervention patients, 12 out of 39 control patients, p ≤ 0.001) at the 1-month follow-up, and 64% (11 out of 15 intervention patients, 17 out of 29 control patients, p ≤ 0.001) at the 6-month follow-up irrespective of group allocation. In some patients previously resolved errors recurred during follow-up visits. This emphasizes the need for periodical reevaluation of patient administration skills and the provision of prevention strategies besides education.

Conclusion

Patient education that included demonstration of administration skills and verbal and written counseling on observed errors improved eye-drop administration skills irrespective of the communication technique applied. Whereof, high drop-out rates limited the power to detect a difference between groups. In particular, periodic demonstration of administration skills seemed important for sustainable improvement of administration skills. However, further error prevention strategies such as additional education materials or support by a caregiver may be necessary in some patients.

Prospective study comparing Xalatan® eye drops and two similar generics as to the efficacy and safety profile

PURPOSE

To evaluate the efficacy and safety between two generic prostaglandins Lataz-Xalaprost (Greece) and the corresponding original drops (Xalatan^®).

MATERIAL AND METHODS

In this prospective randomized study, 60 patients diagnosed with open-angle glaucoma or ocular hypertension were enrolled, who had never received antiglaucoma treatment. Subjects were divided randomly into three groups (Xalatan, Lataz, and Xalaprost groups) and they were studied over 16 weeks. At each visit, the mean applanation tonometry values and tear break-up time were measured. The Ocular Surface Disease Index questionnaire was used to evaluate patient's symptoms.

RESULTS

There was a statistically significant difference (p < 0.001) in the mean values of the intraocular pressure between the baseline and the last visit (Xalatan group: from 23.11 ± 1.61 mmHg to 15.81 ± 1.22 mmHg, Lataz group: from 23.26 ± 1.33 mmHg to 15.80 ± 1.47 mmHg, and Xalaprost group: from 23.08 ± 1.45 mmHg to 16.08 ± 1.38 mmHg). Both generic eye drops showed mean percentage intraocular pressure reduction comparable to the standards of prostaglandin analogues (Xalatan: 31.57%, Lataz: 32.06%, and Xalaprost: 30.34%). Xalatan reduced the tear break-up time less, followed by Lataz and then by Xalaprost (Xalatan: from 8.5 to 8 s, Lataz: from 8.2 to 7.4 s, and Xalaprost: from 8.7 to 7.7 s). Xalatan presented the best safety profile, followed by Lataz and least was Xalaprost, according to Ocular Surface Disease Index questionnaire's results.

CONCLUSION

No significant difference was recorded in the effectiveness of each generic prostaglandin compared to the original. Furthermore, no patient had to change medication. The differences that arose in the safety profile of the three eye drops suggest a prompt closer initial monitoring of patients who are administered generic eye drops.

Squeeze Me if You Can: Variability in Force Requirements to Extract a Drop From Common Glaucoma Bottles

PURPOSE

To determine the force requirements to dispense a single drop from commonly prescribed brand and generic topical glaucoma medications and correlate these findings with pinch strength in a representative patient population.

PATIENTS AND METHODS

Four bottles of each medication were tested: 2 in the vertical and 2 in the horizontal orientation. Bottles were housed in a customized force gauge apparatus designed to mimic ballpoint fingertip contact with a bottle tip. For all bottles, each of the first 10 dispensed drops was tested and then tests were performed in increments of 10 until the bottle was empty. For each tested drop, the maximum force and displacement were electronically measured. Concurrently, maximum pinch strength was measured on consecutive glaucoma patients.

RESULTS

A total of 84 bottles from 21 bottle designs were tested. There was significant variability across the designs, with roughly a 7-fold (0.67 to 4.49 kgf) and 4-fold (0.81 to 3.00 kgf) difference in force requirements in the vertical and horizontal positions, respectively. Of 53 enrolled patients in the glaucoma clinic, the mean pinch strength was 5.05 (range, 1.23 to 10.4 kgf) and 4.82 (range, 1.47 to 10.67 kgf) kgf for the right and left hands, respectively.

CONCLUSIONS

There is statistically significant variability in the force required to squeeze a drop from common glaucoma medications, and a representative sampling of clinic patients suggests that many likely struggle with the force requirements of several bottle designs. These data further support standardization of topical glaucoma drug delivery and design.

Aids for eye drop administration

One aspect to eye drop adherence is successful instillation of the drops; however, it is well known that many patients struggle with this task. Difficulties may include aiming their drops, extending their neck, preventing excess drop leakage, avoiding contamination of the bottle tip, and generating enough force to expel a drop from the bottle. Instillation aids are devices that aim to ameliorate one or more of these barriers. We review the literature on instillation aids to describe the options available to patients and to report evaluations of their efficacy. Most instillation aids studied improved objective or subjective outcomes of eye drop instillation, including improved rates of successful administration and increased patient satisfaction compared with standard eye-drop bottles. Although further research is warranted, instillation aids may be an underutilized resource for the many patients who struggle to administer their own eye drops.

An upright eyedrop bottle: accuracy, usage of excess drops, and contamination compared to a conventional bottle

Purpose

This study tested the feasibility of using an upright eyedrop bottle (UEB), a device designed to assist patients with eyedrop placement without reclining their head.

Patients and methods

Experienced eyedrop users were enrolled who answered “yes” to the question, “Do you ever have trouble getting your eyedrops in?” After being shown a multimedia presentation and answering a questionnaire regarding eyedrop usage, participants were observed instilling eyedrops. Participants were instructed to instill a single eyedrop in each eye with both a standard bottle and the UEB. They repeated this process three times. With each trial, the amount of time taken to instill drops was recorded, as well as whether a drop landed in the eye (accuracy), if excess drops were used, and if the bottle tip was contaminated.

Results

Forty participants were enrolled, with an average age of 72.4±8.9 years; the majority were females (24 females). Thirty-four participants had been using eyedrops for at least 1 year. The time required to instill eyedrops was significantly less with the UEB in the second and third trials. There was no difference in accuracy between the conventional bottle and the UEB in the left or right eye in any trials. Significantly more participants used excess number of drops while using the conventional bottle in both the left and right eyes in all three trials. The bottle tip was never contaminated with the UEB. Depending on the trial and the eye, the conventional bottle was contaminated by between 42% and 53% of participants.

Conclusion

The UEB has the potential to assist patients with eyedrop placement. Although there was no difference in accuracy between the UEB and the conventional bottle, the UEB was associated with less use of excess drops and less contamination of the bottle tip, compared to the conventional bottle.

Generic drugs for the treatment of ocular conditions: changing the treatment landscape

As global spending on medicinal products continues to rise, the availability of lower-cost generic substitutes is increasingly driving health care decision-making. US FDA does not require strict demonstration of human bioequivalence and/or therapeutic studies for the approval of generic ophthalmic compounds. Bioequivalence between generic and innovator compounds is presumed on the basis of matching active and inactive ingredient profiles. Generic compounds may differ from innovator agents with regards to performance under environmental stress, relative acidity and bottle size/rigidity. Matching ingredient profiles may therefore not result in consistently comparable drug compositions and clinical effects.

Safeguarding the process of drug administration with an emphasis on electronic support tools

AIMS

The aim of this work is to understand the process of drug administration and identify points in the workflow that resulted in interventions by clinical information systems in order to improve patient safety.

METHODS

To identify a generic way to structure the drug administration process we performed peer-group discussions and supplemented these discussions with a literature search for studies reporting errors in drug administration and strategies for their prevention.

RESULTS

We concluded that the drug administration process might consist of up to 11 sub-steps, which can be grouped into the four sub-processes of preparation, personalization, application and follow-up. Errors in drug handling and administration are diverse and frequent and in many cases not caused by the patient him/herself, but by family members or nurses. Accordingly, different prevention strategies have been set in place with relatively few approaches involving e-health technology.

CONCLUSIONS

A generic structuring of the administration process and particular error-prone sub-steps may facilitate the allocation of prevention strategies and help to identify research gaps.

Synergistic Combination of an In-office Procedure and Home Regimen for the Treatment of Facial Hyperpigmentation

Hyperpigmentation disorders, such as melasma and solar lentigines, pose a significant treatment challenge for most patients. Combining a series of in-office procedures, such as chemical peels and light- and laser-based treatments, with maintenance therapies have been shown to provide greater efficacy than one treatment alone. However, receiving multiple in-office procedures may be cost prohibitive for patients. A series of eight case studies were conducted to evaluate the efficacy and tolerability of a novel treatment regimen combining one in-office superficial chemical peel procedure followed by a 12-week topical maintenance program consisting of micro-entrapped 4% hydroquinone, tri-retinol, and sunscreen with sun protection factor (SPF) 30+. Patients presented with Fitzpatrick skin types II and III and mild-to-moderate solar lentigines and/or melasma on their facial skin. Physician-graded overall improvement in hyperpigmentation, standardized photography, and patient satisfaction were evaluated at Weeks 4, 8, and 12. At Week 12, all eight patients demonstrated improvements of at least 25 percent in overall facial hyperpigmentation, with six of the patients demonstrating a 50- or 75-percent overall improvement. One hundred percent of the patients rated their experience with the novel treatment regimen as "excellent" or "good" reflecting high patient satisfaction. Standardized photographs also support the physician and patient findings. Results from these case studies demonstrate that this unique treatment regimen combining one in-office procedure followed by 12 weeks of topical maintenance therapy, may provide an effective, simple, and cost-effective option for patients with facial hyperpigmentation.