The Effect of Topical Treatment With Combigan Compared to Timolol and Brimonidine on Pupil Diameter

Study Overview
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Brief Summary
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In this study we will explore the combined effect of Brimonidine and Timolol 0.5% (Combigan) eye drops on pupil dilation. It is a well studied phenoma that Brimonidine and a miotic effect on the pupil, however the combined effect of alpha agonist and beta blocker has not been studied.

Detailed Description
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In this study we will explore the combined effect of Brimonidine and Timolol 0.5% (Combigan) eye drops on pupil dilation. It is a well studied phenoma that Brimonidine and a miotic effect on the pupil, however the combined effect of alpha agonist and beta blocker has not been studied. The study subjects will be examined twice, two weeks apart. On the first exam the subject will receive Combigan eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops. On the second exam the subject will receive Timolol (0.5%) eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops.

Official Title
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The Effect of Topical Treatment With Combigan Compared to Timolol and Brimonidine on Pupil Diameter

Conditions
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Healthy

Intervention / Treatment
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* Drug: Combigan (Combination of Brimonidine and Timolol)
* Drug: Timolol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy adults subjects with no ocular pathology Non pregnant women Normal pupil response Exclusion Criteria: Chronic topical treatment Systemic medication affecting autonomic nerve system History of intra-ocular surgery Irregular pupil History of ocular neurological or severe cardio-vascular disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Combination of Brimonidine and Timolol<br>On the first exam the subject will receive Combigan (Combination of Brimonidine and Timolol) eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops. On the second exam the subject will receive Timolol (0.5%) eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops. | Drug: Combigan (Combination of Brimonidine and Timolol)<br>* On the first exam the subject will receive Combigan (Combination of Brimonidine and Timolol) eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops. On the second exam the subject will receive Timolol (0.5%) eye drop to the right eye and a Brimonidine drop to the left eye. The effect on pupil size before and 30 minutes, 60 minutes, 240 minutes, and 300 minutes after instillation of eyedrops.<br>* Other names: Combigan;Drug: Timolol<br>* 0.5% eye drop<br>* Other names: Tiloptic;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pupil diameter |  | two weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pupil diameter, Brimonidine, Timolol, Combigan