A combination solution for routine pupillary dilation.
BACKGROUND
This study investigated the ability of a combination drop containing reduced concentrations of tropicamide and phenylephrine to produce pupillary dilation adequate for routine fundoscopy.


METHODS
One eye of each subject (N = 28; age range, 21 to 40 years; median, 23 years) was dilated with 1 drop of a solution containing 0.5% tropicamide and 2.5% phenylephrine (0.5T/2.5P). The other eye was dilated with 1 drop of either of 2 mixtures: 0.5% tropicamide and 1.25% phenylephrine (0.5T/1.25P, N = 15; median age, 23 years), or 0.25% tropicamide and 1.25% phenylephrine (0.25T/1.25P, N = 13; median age, 23 years). A topical anesthetic was administered before instilling the mydriatic agents. Pupil diameter was measured from a flash photograph taken every 15 minutes for 3 hours. There was no significant difference in pupil diameter between eyes dilated with the 0.5T/1.25P test solution and the 0.5T/2.5P control solution for the first 75 minutes after instillation (P = 0.41). All pupils reached their maximum diameter 60 minutes after drop instillation; where no significant difference was observed between the 3 mydriatic solutions (P = 0.81). All pupils were at least 7 mm in diameter 30 minutes after drop instillation, and this size was maintained for at least another 75 minutes for all solutions.


CONCLUSIONS
Combination preparations of reduced concentrations of tropicamide and phenylephrine can produce clinically adequate mydriasis.
Krumholz
David M
DM
Department of Clinical Sciences, State University of New York, State College of Optometry, New York, New York 10036, USA. dkrumholz@sunyopt.edu
Portello
Joan K
JK
Rosenfield
Mark
M
Rosenbaum
Jacob D
JD
D000328:Adult; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D006801:Humans; D008297:Male; D009184:Mydriatics / Q000008:administration & dosage*; D009883:Ophthalmic Solutions; D009887:Ophthalmoscopy / Q000379:methods; D010656:Phenylephrine / Q000008:administration & dosage*; D011680:Pupil / Q000187:drug effects*; D014331:Tropicamide / Q000008:administration & dosage*
D004338:Drug Combinations; D009184:Mydriatics; D009883:Ophthalmic Solutions; D010656:Phenylephrine; D014331:Tropicamide