Korean J Ophthalmol.  2009 Mar;23(1):40-42. 10.3341/kjo.2009.23.1.40.

The Comparison of Mydriatic Effect Between Two Drugs of Different Mechanism

• Park JH
• Lee YC
• Lee SY

• KMID: 1115650
• DOI: http://doi.org/10.3341/kjo.2009.23.1.40

Abstract

PURPOSE: To maximize effective use of mydriatic drugs through comparing the pupillary dilation effects between 1% tropicamide and 2.5% phenylephrine.
METHODS
Fifty people requiring pupillary dilation were divided into 3 groups. Group 1 was treated with one drop of 1% tropicamide in the right eye and one drop of 2.5% phenylephrine in the left eye. Group 2 was treated twice during a 5-minute interval with 1% tropicamide in the right eye. Group 3 was treated twice during a 5-minute interval with 2.5% phenylephrine in the right eye. Groups 2 and 3 were treated with 2.5% phenylephrine and 1% tropicamide in the left eye, administered during a 5-minute interval. The pupillary size was measured in all groups for 40 minutes following eye drops administration.
RESULTS
The mean patient age was 15.7 years. Group 1 included 10 patients, and groups 2 and 3 included 20 patients each. Eight patients in group 1 and 16 patients in group 2 developed a larger right pupil. Fourteen patients in group 3 developed a larger left pupil.
CONCLUSIONS
Our study showed that 1% tropicamide, with its parasympathetic antagonistic mechanism of action, was more effective at inducing pupillary dilation than 2.5% phenylephrine, and the combination of 1% tropicamide and 2.5% phenylephrine was more effective than multiple drops of single eye drops.

Keyword

Pupil dilation; 1% tropicamide; 2.5% phenylephrine

MeSH Terms

Adolescent
Adult
Child
Child, Preschool
Dose-Response Relationship, Drug
Drug Administration Schedule
Female
Follow-Up Studies
Humans
Male
Muscarinic Antagonists/*administration & dosage
Mydriatics/*administration & dosage
Ophthalmic Solutions
Phenylephrine/*administration & dosage
Pupil/*drug effects
Refractive Errors/diagnosis/physiopathology
Retrospective Studies
Tropicamide/*administration & dosage
Young Adult

Figure

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  Fig. 1 The eye where the maximal pupillary diameter was significantly larger.

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