The Effect of Brimonidine

Wake Forest University (WFU)

Status and phase: Completed; Phase 4

Conditions: Intraocular Pressure

Treatments: Drug: Phenylephrine Ophthalmic Product; Drug: Brimonidine; Drug: Tropicamide

Study type: Interventional

Funder types: Other

Identifiers

NCT03959176

IRB00058366

Details and patient eligibility

About

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.

Full 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.

Enrollment: 13 patients

Sex: All

Ages: 18 to 50 years old

Volunteers: Accepts Healthy Volunteers

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)

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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13 participants in 2 patient groups

Group 1

Experimental group

Description:

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.

Treatment:

Drug: Phenylephrine Ophthalmic Product

Drug: Tropicamide

Drug: Brimonidine

Group 2

Experimental group

Description:

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.

Treatment:

Drug: Phenylephrine Ophthalmic Product

Drug: Tropicamide

Drug: Brimonidine