title: The effect of drop vehicle on the efficacy and side effects of topical glaucoma therapy: a review.
abstract: OBJECTIVE
  Topically applied medications are frequently used in ophthalmology to treat acute and chronic conditions, and are considered to be safer than their systemically applied counterparts, due to the reduced rate of systemic side effects.
  
  
  RESULTS
  Many experimental and clinical studies have reported that the long-term use of topical medications in chronic ophthalmic conditions, such as glaucoma, may adversely affect the ocular surface. Preservatives play a pivotal role in almost all multidose ophthalmic preparations, inhibiting microbial growth and preserving the active drug. Consequently, preservatives are partially responsible for ocular side effects, although the exact mechanism of these side effects is not known.
  
  
  CONCLUSIONS
  The role of preservatives in the efficacy and side effects of antiglaucoma drugs is reviewed. The recent advances in preservative technologies and their role in decreasing the side effects associated with antiglaucoma drugs are also discussed.
authors.affiliation: Department of Ophthalmology, University of Texas Health Science Center, Houston, Texas 77030, USA. richard.w.yee@uth.tmc.edu
authors.forename: Richard W
authors.initials: RW
authors.lastname: Yee
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000009:adverse effects; D003315:Cornea / Q000187:drug effects* / Q000473:pathology; D003316:Corneal Diseases / Q000139:chemically induced / Q000473:pathology; D005901:Glaucoma / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure / Q000187:drug effects; D014677:Pharmaceutical Vehicles / Q000009:adverse effects*; D011310:Preservatives, Pharmaceutical / Q000009:adverse effects
chemical_list: D000959:Antihypertensive Agents; D014677:Pharmaceutical Vehicles; D011310:Preservatives, Pharmaceutical