title: Co-prescribing of topical and systemic beta-blockers in patients with glaucoma: a quality use of medicine issue in Australian practice.
abstract: OBJECTIVE
  Prescribing topical beta-blockers for patients with glaucoma, who are also being treated with systemic beta-blockers, raises efficacy and safety concerns. This potentially inappropriate co-prescribing practice is a Quality Use of Medicine issue. This study aimed to quantify the extent of co-prescribing of topical and systemic beta-blockers in Australian clinical practice.
  
  
  METHODS
  This is a retrospective analysis of de-identified billing data for supply (surrogate marker for prescribing) of topical and systemic beta-blockers from the Pharmaceutical Benefits Scheme (1999-2004) to concessional patients supplied either topical or systemic beta-blockers. The primary outcome was the percentage of patients supplied systemic beta-blockers within the patient population supplied topical beta-blockers. This percentage was calculated for each financial year (July 1999-June 2004), age group (<65 years; 65-74 years; 75-84 years; > or =85 years) and sex.
  
  
  RESULTS
  Approximately 20% of patients supplied topical beta-blockers (representing Australian glaucoma patients) were also supplied systemic beta-blockers, equating to more than 20 000 patients per year. This percentage varied with age, but not with year or sex. The percentage of patients co-supplied topical and systemic beta-blockers was the lowest (13%) for patients <65 years and the highest (23%) for patients 75-84 years.
  
  
  CONCLUSIONS
  Pharmaceutical Benefits Scheme supply data shows that the potentially inappropriate practice of co-prescribing topical and systemic beta-blockers affects more than 20 000 concessional patients in Australia each year, particularly the elderly. This Quality Use of Medicine issue has now been quantified; doctors, pharmacists and patients must be made aware of the reduced efficacy and potential for more side-effects from this co-prescribing practice.
authors.affiliation: Department of Ophthalmology, Sydney Eye Hospital, University of Sydney, Sydney, New South Wales, Australia. eyegoldberg@gmail.com
authors.forename: Ivan
authors.initials: I
authors.lastname: Goldberg
authors.forename: Michael A
authors.initials: MA
authors.lastname: Adena
mesh_terms: D000287:Administration, Topical; D000319:Adrenergic beta-Antagonists; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D011307:Drug Prescriptions / Q000706:statistics & numerical data*; D017723:Drug Utilization Review / Q000706:statistics & numerical data*; D005260:Female; D005901:Glaucoma / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009313:National Health Programs / Q000706:statistics & numerical data; D010604:Pharmacy / Q000706:statistics & numerical data*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D019984:Quality Indicators, Health Care; D012189:Retrospective Studies; D017678:Sex Distribution
chemical_list: D000319:Adrenergic beta-Antagonists