title: The effects of phenylephrine 2.5% versus phenylephrine 10% on pupillary dilation in patients with diabetes.
abstract: OBJECTIVE
  A prospective, double-blind study was conducted to compare the clinical efficacy of a combination of 1% tropicamide and 2.5% phenylephrine and a combination of 1% tropicamide and 10% phenylephrine for pupillary dilation in patients with diabetes.
  
  
  METHODS
  Either 2.5% phenylephrine in one eye and 10% phenylephrine in the other eye, 2.5% phenylephrine in both eyes, or 10% phenylephrine in both eyes was administered to 127 consecutive patients with diabetes. All patients received 1% tropicamide in both eyes.
  
  
  RESULTS
  There was no statistically significant difference in the amount of pupillary dilation between the three groups.
  
  
  CONCLUSIONS
  As 2.5% phenylephrine may produce a lower incidence of side effects than the 10% concentration, we advise the use of the lower concentration, particularly among patients with diabetes, who already exhibit a higher prevalence of vascular disease and autonomic dysfunction.
authors.affiliation: Kresge Eye Institute, Detroit, Michigan 48201, USA.
authors.forename: J S
authors.initials: JS
authors.lastname: Weiss
authors.forename: J N
authors.initials: JN
authors.lastname: Weiss
authors.forename: D S
authors.initials: DS
authors.lastname: Greenfield
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003920:Diabetes Mellitus / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000503:physiopathology*; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions; D010656:Phenylephrine / Q000008:administration & dosage / Q000494:pharmacology*; D011446:Prospective Studies; D011680:Pupil / Q000187:drug effects*; D014331:Tropicamide / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D009883:Ophthalmic Solutions; D010656:Phenylephrine; D014331:Tropicamide