title: [Monitoring medication errors in an internal medicine service].
abstract: BACKGROUND
  Patients admitted to internal medicine services receive multiple drugs and thus are at risk of medication errors.
  
  
  OBJECTIVE
  To determine the frequency of medication errors (ME) among patients admitted to an internal medicine service of a high complexity hospital.
  
  
  METHODS
  A prospective observational study conducted in 225 patients admitted to an internal medicine service. Each stage of drug utilization system (prescription, transcription, dispensing, preparation and administration) was directly observed by trained pharmacists not related to hospital staff during three months. ME were described and categorized according to the National Coordinating Council for Medication Error Reporting and Prevention. In each stage of medication use, the frequency of ME and their characteristics were determined.
  
  
  RESULTS
  A total of 454 drugs were prescribed to the studied patients. In 138 (30,4%) indications, at least one ME occurred, involving 67 (29,8%) patients. Twenty four percent of detected ME occurred during administration, mainly due to wrong time schedules. Anticoagulants were the therapeutic group with the highest occurrence of ME.
  
  
  CONCLUSIONS
  At least one ME occurred in approximately one third of patients studied, especially during the administration stage. These errors could affect the medication safety and avoid achieving therapeutic goals. Strategies to improve the quality and safe use of medications can be implemented using this information.
authors.forename: Ann-Loren M
authors.initials: AL
authors.lastname: Smith
authors.forename: Inés  A
authors.initials: I
authors.lastname: Ruiz
authors.forename: Marcela  A
authors.initials: M
authors.lastname: Jirón
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007388:Internal Medicine / Q000592:standards / Q000706:statistics & numerical data*; D008297:Male; D008508:Medication Errors / Q000517:prevention & control / Q000706:statistics & numerical data*; D008875:Middle Aged; D011446:Prospective Studies