title: Identifying widely covered drugs and drug coverage variation among Medicare part D formularies.
abstract: BACKGROUND
  Clinicians can find it difficult to know which drugs are covered for their Medicare patients because formularies vary widely among Medicare Part D plans and many states have 50 or more such plans.
  
  
  OBJECTIVE
  To determine whether Part D formularies in California (the state with the most Medicare beneficiaries) and Hawaii have at least 1 drug within each of 8 treatment classes for hypertension, hyperlipidemia, and depression that can be identified for clinicians as "widely covered" by the vast majority of Part D plans.
  
  
  METHODS
  Use of the medicare.gov Web site (March 1-April 15, 2006) to examine 72 California and 43 Hawaii Part D formularies' coverage of 8 treatment classes (angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, beta-blockers, calcium channel blockers, loop diuretics, selective serotonin reuptake inhibitors, statins, and thiazide diuretics), with evaluation of how often drugs were widely covered (defined as inclusion in >or=90% of formularies at co-payments of <or=$35 without prior authorization).
  
  
  METHODS
  Identification of treatment classes with at least 1 widely covered drug.
  
  
  RESULTS
  For California, coverage for the 75 drugs examined ranged from 7% to 100%. Despite this variation, 7 of 8 classes (excluding angiotensin II receptor blockers) had at least 1 widely covered drug. Of the 34 widely covered drugs (45%), all but 2 were generic. Restricting widely covered to include 95% or more of formularies at co-payments of $15 or less still resulted in 7 of 8 classes with at least 1 widely covered drug. Overall, 73% of generic drugs and 6% of brand-name drugs were widely covered. Findings were similar for Hawaii.
  
  
  CONCLUSIONS
  Formularies varied substantially; however, all but 1 treatment class examined had 1 or more widely covered drugs at low co-payments. Knowing which drugs are widely covered would assist clinicians in prescribing, since not all generic drugs were widely covered. Clinicians should know that few brand-name drugs are widely covered and check coverage before prescribing.
authors.affiliation: Department of Family Medicine and Community Health, John A. Burns School of Medicine at University of Hawaii, Honolulu, USA. cwtseng@hawaii.edu
authors.forename: Chien-Wen
authors.initials: CW
authors.lastname: Tseng
authors.forename: Carol M
authors.initials: CM
authors.lastname: Mangione
authors.forename: Robert H
authors.initials: RH
authors.lastname: Brook
authors.forename: Emmett
authors.initials: E
authors.lastname: Keeler
authors.forename: R Adams
authors.initials: RA
authors.lastname: Dudley
mesh_terms: D000959:Antihypertensive Agents / Q000145:classification / Q000191:economics; D002140:California; D016527:Drug Costs; D004363:Drug Utilization; D016568:Drugs, Generic / Q000191:economics; D005569:Formularies as Topic; D006254:Hawaii; D007356:Insurance, Pharmaceutical Services; D020407:Internet; D006278:Medicare; D014481:United States
chemical_list: D000959:Antihypertensive Agents; D016568:Drugs, Generic