title: Improved Presbyopic Vision With Miotics.
abstract: OBJECTIVE
  To evaluate the efficacy of using a parasympathomimetic drug (carbachol) with an alpha agonist (brimonidine) to create optically beneficial miosis to reduce the effect of presbyopia.
  
  
  METHODS
  In this prospective, double-masked, randomized, placebo-controlled clinical trial, 48 naturally emmetropic and presbyopic subjects aged between 43 and 56 years with an uncorrected distance visual acuity of at least 20/20 in both eyes without additional ocular pathology were eligible for inclusion. Subjects were divided into 2 groups. The treatment group (n=30 eyes) received single dose of 2.25% carbachol plus 0.2% brimonidine eye drops. The control group (n=18 eyes) received placebo drops. Drops were given to all subjects in a masked fashion, in their nondominant eye. The minimum posttreatment follow-up was 3 months. The subjects' pupil size and both near and distance visual acuities were evaluated before and after treatment at 1, 2, 4, 8, and 10 hr, by a masked examiner at the same room illumination.
  
  
  RESULTS
  Statistically significant improvement in near visual acuity was achieved in all subjects who received carbachol plus brimonidine drops (P<0.0001). In this masked study, all subjects liked and would use this therapy if it was available. None would use the placebo. There was no evidence of tolerance or tachyphylaxis during the study period.
  
  
  CONCLUSIONS
  Improving the depth of focus by making the pupil smaller caused statistically significant improvement in near visual acuity in emmetropic presbyopic subjects. Carbachol plus brimonidine seem to be an acceptable and safe alternative to corrective lenses and surgical procedures.
authors: Department of Ophthalmology, Faculty of Medicine, Al-Azhar University, Cairo, Egypt.
authors: Almamoun
authors: A
authors: Abdelkader
mesh_terms: D000328:Adult; D000367:Age Factors; D000068438:Brimonidine Tartrate / Q000494:pharmacology*; D002217:Carbachol / Q000494:pharmacology*; D003867:Depth Perception / Q000187:drug effects; D004311:Double-Blind Method; D058453:Emmetropia / Q000187:drug effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008916:Miotics / Q000494:pharmacology*; D011305:Presbyopia / Q000188:drug therapy* / Q000503:physiopathology; D011446:Prospective Studies; D011680:Pupil / Q000187:drug effects; D012029:Refraction, Ocular / Q000187:drug effects; D014792:Visual Acuity / Q000187:drug effects*
chemical_list: D008916:Miotics; D000068438:Brimonidine Tartrate; D002217:Carbachol