The Effect of Brimonidine
Study Details
Study Description
Brief Summary
This study will evaluate whether pre-treating patients with Brimonidine 0.2% before and/or after dilating the pupils will help to control the changes in intraocular pressure often seen when using dilating drops. The study will also evaluate the effects of different sequences of administering dilating drops along with Brimonidine on pupil size and reactivity.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Phase 4 |
Detailed Description
Intraocular pressure (IOP) can fluctuate due to various external factors such as exercise, medications, and eye movements. Although it is considered natural for IOP to fluctuate daily, prolonged increases in IOP can be harmful. Sustained elevated IOP has been linked to optic nerve damage and glaucoma. Mydriatic drops routinely given to dilate pupils in patients in need of an eye exam have been known to increase IOP. In practice, a combination of drugs are used to achieve pupil dilation needed for routine eye exams or in perioperative situations. The use of Tropicamide 1% and Phenylephrine 2.5% are known to be safe and effective options for dilating the pupils when used in conjunction with one another, but these drugs can increase IOP. Drugs such as Brimonidine, a selective alpha-2 agonist, are known to reduce IOP through several different methods. This study seeks to understand the effects of Brimonidine used along with Tropicamide and Phenylephrine to control IOP.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Group 1 The right eye will receive a sham drop followed by 1 drop of Tropicamide 1%/Phenylephrine 2.5% five minutes after the sham drop is administered. A one minute wait will occur followed by a second drop of Tropicamide 1%/Phenylephrine 2.5%. The left eye will receive 2 drops of Brimonidine 0.2% followed by a five minute wait time. One drop of Tropicamide 1%/Phenylephrine 2.5% will then be administered followed by a one minute wait time. A second drop of Tropicamide 1%/Phenylephrine 2.5% will be administered. |
Drug: Brimonidine
2 drops administered once in the left eye in both study arms
Other Names:
Drug: Tropicamide
1 drop administered at two different times points in both eyes in both study arms
Other Names:
Drug: Phenylephrine Ophthalmic Product
1 drop administered at two different time points in both eyes in both study arms
|
| Experimental: Group 2 The right eye will receive 1 drop of Tropicamide 1%/Phenylephrine 2.5% followed by a one minute wait. A second drop of Tropicamide 1%/Phenylephrine 2.5% will be administered followed by a 15 second wait after which a sham drop will be administered. The left eye will receive 1 drop of Tropicamide 1%/Phenylephrine 2.5% followed by a one minute wait. A second drop of Tropicamide 1%/Phenylephrine 2.5% will then be administered followed by a 15 second wait after which 2 drops of Brimonidine will be administered. |
Drug: Brimonidine
2 drops administered once in the left eye in both study arms
Other Names:
Drug: Tropicamide
1 drop administered at two different times points in both eyes in both study arms
Other Names:
Drug: Phenylephrine Ophthalmic Product
1 drop administered at two different time points in both eyes in both study arms
|
Outcome Measures
Primary Outcome Measures
- Intraocular Pressure [Baseline (Pre drop administration)]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
- Intraocular Pressure [15 minutes post drop administration]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
- Intraocular Pressure [30 minutes post drop administration]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
- Intraocular Pressure [1 hour post drop administration]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
- Intraocular Pressure [2 hour post drop administration]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
- Intraocular Pressure [4 hour post drop administration]
To observe how differing the sequence of administration of Tropicamide 1%/Phenylephrine 2.5% and Brimonidine 0.2% influences intraocular pressure.
Secondary Outcome Measures
- Pupil Size [Baseline (Pre drop administration)]
Pupil size measurement
- Pupil Size [15 minutes post drop administration]
Pupil size measurement.
- Pupil Size [30 minutes post drop administration]
Pupil size measurement
- Pupil Size [1 hour post drop administration]
Pupil size measurement.
- Pupil Size [2 hours post drop administration, 4 hours post drop administration]
Pupil size measurement.
- Pupil Size [4 hours post drop administration]
Pupil size measurement
- Pupil Reaction to Light [Baseline (Pre drop administration)]
Pupil reaction to light will be measured as none, poor or brisk.
- Pupil Reaction to Light [15 minutes post drop administration]
Pupil reaction to light will be measured as none, poor or brisk.
- Pupil Reaction to Light [30 minutes post drop administration]
Pupil reaction to light will be measured as none, poor or brisk.
- Pupil Reaction to Light [1 hour post drop administration]
Pupil reaction to light will be measured as none, poor or brisk.
- Pupil Reaction to Light [2 hours post drop administration]
Pupil reaction to light will be measured as none, poor or brisk.
- Pupil Reaction to Light [4 hours post drop administration]
Pupil reaction to light will be measured as none, poor or brisk.
Eligibility Criteria
Criteria
Inclusion Criteria:
-
Healthy individuals
-
Females of childbearing potential must agree to use a reliable method of birth control while participating in the study.
Exclusion Criteria:
-
Diabetic
-
Have a history of glaucoma
-
Have a history of iris trauma
-
Have a history of eye surgery except for LASIK or PRK
-
Pregnant
-
Anisocoria (unequal pupils)
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Wake Forest Baptist Medical Center | Winston-Salem | North Carolina | United States | 27157 |
Sponsors and Collaborators
- Wake Forest University Health Sciences
Investigators
- Principal Investigator: Keith Walter, MD, Wake Forest Baptist Medical Center
Study Documents (Full-Text)
More Information
Publications
None provided.- IRB00058366