title: [Divisibility of warfarin and fluindione tablets tested in elderly patients and their family circle].
abstract: BACKGROUND
  Vitamin K antagonist tablets are often split to fractionate the dose by elderly patients. We performed a study in order to assess the divisibility of one dosage strength of score-lined warfarin and of score-lined fluindione.
  
  
  METHODS
  Due to a recent change in the pharmaceutical form of fluindione in order to improve the divisibility, the study was performed over 2 different periods (with the « old » and with the « new » pharmaceutical form). In each period, 10 patients mean aged 82 years, 10 relatives, 10 nurses, 10 medical doctors) were asked to split in half warfarin tablets (W2 1(st) period et W2 2(d) period) and fluindione tablets (F2 et F'2), and to split fluindione tablets into 4 fragments (F4 et F'4). The first end-point was the accuracy of splitting estimated by the difference between the real and the expected weight of fragmented tablets. The statistical analysis was performed using an ANOVA test with 2 variables, subject and drug. The difference between the 2 periods were analyzed using an ANOVA test with 2 variables, subject and period.
  
  
  RESULTS
  Over the 2 periods, the differences between real and expected weight were of 4.65% for W2 1(st) phase, 9.48% for F2, 15.35% for F4, 5.56% for W2 2(d )period, 4.30% for F'2, and 6.98% for F'4. The quality of splitting was statistically poorer in the elderly patient group compared to other subjects.
  
  
  CONCLUSIONS
  This study was not design to assess the clinical relevance (bleeding or thromboembolism) or the anticoagulation control of the variations in drug mass due to inappropriate splitting of tablets. However, split form of drugs should be prescribe with caution to elderly patients.
authors.affiliation: Unité gériatrique aiguë,Unité gériatrique aiguë,Unité gériatrique aiguë,Unité gériatrique aiguë. eric.pautas@cfx.aphp.fr
authors.forename: Eric
authors.initials: E
authors.lastname: Pautas
authors.forename: Jérémie
authors.initials: J
authors.lastname: Despres
authors.forename: Isabelle
authors.initials: I
authors.lastname: Peyron
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Golmard
authors.forename: Jennifer
authors.initials: J
authors.lastname: Grange
authors.forename: Nelly
authors.initials: N
authors.lastname: Koenig
authors.forename: Adeline
authors.initials: A
authors.lastname: Gouronnec
authors.forename: Nathalie
authors.initials: N
authors.lastname: Mitha
authors.forename: Virginie
authors.initials: V
authors.lastname: Siguret
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gouin-Thibault
mesh_terms: D000203:Activities of Daily Living / Q000145:classification; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000008:administration & dosage* / Q000009:adverse effects; D017028:Caregivers / Q000193:education*; D004305:Dose-Response Relationship, Drug; D016568:Drugs, Generic / Q000008:administration & dosage* / Q000009:adverse effects; D005260:Female; D005602:France; D006801:Humans; D008297:Male; D010353:Patient Education as Topic; D010630:Phenindione / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D012646:Self Administration; D013607:Tablets; D014859:Warfarin / Q000008:administration & dosage* / Q000009:adverse effects
chemical_list: D000925:Anticoagulants; D016568:Drugs, Generic; D013607:Tablets; D010630:Phenindione; D014859:Warfarin; C017673:fluindione